The Go-Between (1/4)
The Go-Between
BBC Sherlock
Rating 12: Non-explicit het
Summary: Sherlock has to come up with a new plan to sort out Magnussen. But he also has to solve the problem of John and Mary.
Many thanks to Kalypso for betaing
Sherlock's second stay in hospital is much longer: several months, in fact. That's less about the doctors' stern warnings to him about his body needing time to recover - there's only one doctor he's ever paid any attention to - and more about the need to avoid clients. Well, one client specifically. Lady Elizabeth Smallwood.
She won't come and visit him in hospital: far too conspicuous. And nor will she risk her phone calls or letters being intercepted. But shortly after he returns to Baker Street, she will doubtless slip discreetly into the flat one evening and demand a progress report. And that will be tricky, to say the least.
Sherlock's broken bad news to clients before - your new wife's run away with her real husband, your cushy job's been set up to cover for a bank robbery - but this is in a different league. I attempted to negotiate with Magnussen about your husband's letters and he pissed in my fireplace. I got into his office by false pretences, but he discovered me in the act, so that he can now link you personally to an attempted cover-up. I currently have no idea on how to access the Appledore vaults and would not be fit to do so in any event. In my professional opinion, you are royally fucked and you should do whatever Magnussen demands.
The best he can hope for at that point is Lady Smallwood taking him off the case. Even that means Sherlock loses his cover story if Mycroft or Lestrade start asking why he's still sniffing around Magnussen. Far worse is the likely consequence of the one other detail he'll have to include in his report to Lady Smallwood. When I was in Magnussen's office someone shot me. Magnussen may call Lady Smallwood an old woman, but Sherlock knows just how dangerous old women can be. Especially if they start asking awkward questions, like: Who could be gunning for Magnussen, but decide to shoot you instead?
Lestrade's being deliberately, helpfully clueless about the whole incident. Accepted Sherlock's statement that his attacker was masked, that it was all a blur and he can't remember any details about him or her. Presumably accepted whatever lies Magnussen has told in his witness statement. Lestrade will send his team off on a few wild goose chases and then let the case go cold. And why would Donovan be interested in catching someone who shot Sherlock, except to give them a medal? No problem there.
If anyone focuses properly on the case, though, they might deduce - or at least guess - that Sherlock is protecting his attacker, and that narrows down the field of suspects drastically. And Lady Smallwood, beneath her genteel facade, is both tough and sharp. If it's clear that Sherlock can't handle Magnussen, she might try to do so herself, and Sherlock doesn't need any more unexpected female interventions.
He's fairly confident though that she won't act before she's talked to him, heard exactly what he learned from Magnussen. So he needs to stay in hospital - heroically suffering the consequences of his efforts on her behalf - until he's found a solution to the problem. Then he can make a rapid recovery, and when Lady Smallwood does come calling, reassure her that the whole situation is under control.
Well, that's the theory: now he just has to fill in the details, such as being able to leave the hospital without collapsing, and the actual taking down of Magnussen. And, of course, it’s not the only situation Sherlock has to get under control. Because the other problem - perhaps even the more urgent one - is what to do about John and Mary’s estrangement.
***
John's making even more hospital visits the second time round. Probably worrying that, if he takes his eyes off Sherlock for too long, he'll abscond again. Mary's there frequently as well, presumably as some kind of atonement. It takes far too long for Sherlock's morphine-fuddled brain to realise that they're visiting him in shifts: he gets John or Mary but rarely John-and-Mary. And even longer to work out that the shifts are so that they avoid each other. That John can't bear even to say goodbye to Mary as she leaves; that Mary keeps looking at her watch during her visits not because she's bored, but because she's trying to work out how long she's got before John turns up.
Mary's still working at her old surgery; John's quit and got a job with an out-of-hours service. He's not cycling to work anymore, which is good, because he'd be a danger to himself in his current state of mental confusion. But he's lost weight, even with less exercise. He talks about old cases, especially the unsolved ones, as if that's going to help anchor Sherlock to life, encourage him to recover. Sherlock has a speech planned for the day John finally does want to talk about Mary - he's quite proud of how compassionate he sounds - but so far there's been no good opportunity to use it. John has to be allowed to brood for a while first.
Sherlock can at least drop a few hints. John's oddly relieved when he turns up one day to see that The Coat is back, as if it's a symbol for Sherlock's own eventual restoration.
"As good as new," Sherlock says. "Anthea knows a dry-cleaner who's exceptionally good at removing blood stains. She sends you her love, by the way."
For a moment a sentimental smile hovers on John's expressive face, and then it's gone.
"She probably doesn't remember who I am. We only met briefly," he says hastily. "And her name's not Anthea, anyhow."
All true, of course, but it's still worth reminding John about her. Because when John asked out Anthea, all he knew about her was that she had a fake name and was working for a man whom he believed to be a criminal mastermind. If Sherlock had been paying more attention when he first heard that story, he should have realised what John's type of woman was.
Looking back, he wonders how he ever missed the signs. John decided he wanted a second date with Sarah after she helped him fight Chinese gangsters, and wasn't the one with the nose some kind of mountain-climber? He remembers vaguely some unfortunate comment of his about whether she actually needed an ice-axe. As for the one with the spots, who would have thought a woman so afflicted would have had such a complex love-life?
There's another one he's missed, probably several, but there are some of John's ex-girlfriends so boring that John himself couldn't remember basic details about them. The overall pattern remains, however. It's not simply good looks that unite the women John falls hardest for: women with a taste for danger and ones with a mystery surrounding them are more prominent. It's why John's always good at chatting up witnesses in their cases.
Another image abruptly surfaces from his mind. Irene. John quite liked the thought of getting Irene's attention at first, didn't he? Yet another dangerous, mysterious woman. And then he remembers why Irene isn't a good example at all. She hurt Sherlock and John could never forgive her for that. What was it he'd said to her at the power station? How come I can see you, and I don’t even want to? It hadn't simply been jealousy, had it? John can forgive injuries to himself and even people lying to him; it's the only reason their friendship’s survived four and a half years. But enemy of Sherlock is an automatic red flag for John. One of the things Sherlock has to do is demonstrate to John that he doesn't have a problem with Mary. Or at least only a deductive one.
***
For the first few days Mary presumably makes the kind of banal conversation that Sherlock's brain automatically filters out. That leaves him plenty of time to contemplate getting into Appledore. Unfortunately, his first two plans both contain obvious flaws, and he can’t for the moment think of a third one. Time to distract his mind, perhaps, and leave his unconscious to solve the problem. Focus on something trivial, while waiting for inspiration. Like Mary’s knitting technique.
She’s given up talking to him by this point, and just sits by his bed and knits stuff for the baby. She is one of the more hopeless knitters that Sherlock has ever seen and he’s getting frustrated enough by it that he feels the need to explain how it should be done.
"How do you know about knitting?" she asks. "You can't have looked it up on YouTube this time."
"Mummy taught me," he replies. "She was very good. When I was thirteen, she knitted me a Möbius band scarf."
"A what?"
He explains the concept and ends up telling her quite a bit more about Mummy as the days trudge slowly past. She's a good listener, he'll give her that.
***
It’s frustrating how he’s not just tired all the time, but the drugs are also fogging his memory. He has to write things down just to organise his own thoughts, as he slowly starts to climb the mental stairs back up to where he should be. He’s not ready for Appledore, but what about Mary? If he can learn more about her, that might help him clarify what to say to John.
But he can't ask Mary questions, that's the problem. She gave John the flash drive, not him, but John clearly hasn't looked at it yet. So if Mary answers Sherlock's questions, she's giving him information that John doesn't know, which is not going to turn out well. But if he deduces things about Mary himself and then checks his deductions with her, that's OK. Probably OK. He's not brilliant at ethics at the best of times, but it sounds plausible, at least.
What he can ask Mary about, he realises after some consideration, is how she broke in that night, got into Magnussen's penthouse despite all the obstacles. It's not cheating to ask about that: John won't care how Mary did it. That's not what's nagging at his mind.
But as soon as Sherlock actually concentrates, realises what the correct question is, he knows half the answer already. The next time Mary turns up, as she's just sitting down, reaching to pull out the knitting from her bag, he says:
"You had an escape route from Magnussen's penthouse via the outside of the building, so why didn't you come in that way as well, ambush him there? Why enter through his private office and risk being spotted?"
Mary straightens up, and she doesn't have the knitting needles in her hands. Which is just as well, because if you're a trained assassin, you can probably do someone a nasty injury with them. She just looks at him, with that set air to her face that reminds him she is capable of much more violence than most people he knows. But also, perhaps, of showing much more courage.
"And how does someone get past every level of security known to man and into that office?" Sherlock goes on. "By being invited through, like I was. But Janine didn't expect you that night. So who else would have let you waltz up to the top of the building?"
"Sherlock-" she begins, but she doesn't need to tell him the next bit, because he's already deduced it.
"Magnussen wanted to harass you, didn't he, so he invited you up to his penthouse?"
Her hand moves instinctively towards her phone, as if she's remembering that particular message. As if she has to check, even now, that it's been deleted.
"He said he'd had a little chat with you and John," she replies. "I thought...I thought for a moment he'd already told you what I was."
"But he didn't know you were an assassin, surely? Or he’d only have dared meet you in a public place." Or at least in a building with your picture plastered all over it. Even a brilliant man needs to take some precautions.
"He knew Mary Morstan was dead," Mary says slowly. "That was his first message to me. Two weeks after I got engaged."
"What did it say exactly?" he asks, because strictly speaking he's still working on her case and it might help. And he knows she has an excellent memory.
"So sorry about the tragic end of Mary Morstan. Her friends will be devastated. C. A. Magnussen."
"That was the easiest thing to spot, for anyone who was looking," he says, knowing he should have picked it up. "Even orphans have someone around from long ago. A beloved aunt; a friend who helped look after them."
Mary nods. "Magnussen didn't mention any other deaths. And I wasn't gonna sit around and wait while he found where the bodies were buried."
It's hard to plan a murder as well as a wedding, isn't it? She'd been very efficient, making friends with Janine so quickly, but she hadn't been able to use that information. Until Magnussen finally gave her her chance.
"He doesn't expect his victims to fight back," Sherlock says. "Especially the women. That's why he liked the thought of inviting you after he'd just humiliated us. No problem in getting through the outer levels of security. But even so, they must still have checked you before letting you into the building."
He forces his mind back to that image of Mary turning to look at him that night. Don't look at the gun or her face. Dressed all in black, including black hat and gloves. Nothing too unusual there. Body armour and assault vest - bit of a giveaway. "How did you get your equipment past?"
"I had a coat on and I made sure I was looking pretty pregnant. They didn't bother searching me thoroughly, once I'd gone through the metal detector."
"And the gun?"
"I didn't take one. I knew some of the security guards were armed, so I’d be able to steal a weapon.”
Mary's voice now is calm, professional. She's been trained to make rapid decisions, hasn't she? And to fight dirty if necessary. "It was easier than I expected to start with, despite Janine saying the security was ridiculously tight. She'd told me there was another lift - for plebs - up to the top floor, as well as Magnussen's private one. I thought she meant they both went right up to the penthouse. I had an armed guard escorting me and I guessed there'd be a security camera in the lift. But I doubled up as I was coming out of it, like my stomach was hurting me. I'm short, blonde and pregnant; he didn't expect me to attack him."
Her left elbow twitches slightly, and Sherlock is abruptly reminded of Irene smoothly disarming a gunman. He nods. Also explains why the unconscious guard was up on the 32nd floor, not the 31st, where they were normally based.
"But then you realised you'd come out into his office, instead of the penthouse?" Mary had been expecting privacy, but she hadn't understood that Magnussen didn't care what his underlings saw. "And you saw Janine?"
"That was close," she says. "Magnussen must have worked out Janine and me were friends and wanted her to watch me go up to his flat. Because then she'd know he had some dirt on me, and I'd know she knew that. He liked making women suffer."
He can hear the tension in her voice now. Grit in the killing machine; the personal involvement that had distorted her professional judgement.
"Janine was double-checking to make sure that Magnussen was going to stay out of the way for some time," Sherlock comments. "She didn't look round till it was too late."
"I didn't have a choice by that point," Mary says bleakly. "And I'm fast. I have to be. I've always had to be fast and good."
"Good enough to shoot my liver, thus avoiding major arteries, but not to miss the inferior vena cava. You didn't want to kill me, but you knew there was a risk, didn't you?"
Mary shrugs, as if she can't explain her decision exactly even to herself. How much does your training take over automatically in such a stressful situation, Sherlock wonders, as he starts to replay the key moments in his mind. Probably some time since her last hit, but she'd have been trained to kill, not wound, wouldn't she? She could have shot him through the heart and he'd never have left that room. Or his leg, and he'd never have walked properly again. Or his hand and no more violin playing. Easy to say she made a fatal mistake, harder to know what she should have done. What he would have done if he was her? Well, not shot anyone, obviously. Not even sprained anyone.
He thinks he didn't say that last bit out loud. But Mary's presumably been carrying on their conversation - her mouth's open and there's a determined look on her face - so he tunes in to her again.
"I had to shut you up," Mary says, "and you never shut up. Why didn't you let me kill Magnussen?"
"I couldn't-" he begins.
"-or let Lady Smallwood, or whoever you thought I was?"
As if it's his fault that her murder plan was unworkable. Maybe she needs to be reminded of that.
"Did you think you could possibly get away with it?" he announces, and abruptly realises that it's far harder sounding effortlessly superior when you're lying down semi-naked with a drip in your arm. "Your face was uncovered. You'd been seen going into the building, you'd have been seen going out again."
And then his mind catches up with his own words. "Oh, I see. You weren't going to leave, were you? You were going to kill Magnussen and then kill yourself."
There's a snort from Mary, as if she's in pain; but when he focuses, he realises that she's laughing. Even if she does look as if she's about to cry as well.
"Don't be bloody stupid, Sherlock," she says, at last. "I play to win. You don't like musicals, do you? Shame, because Chicago's really good. There's a song in it called 'We Both Reached for the Gun', where a woman talks her way out of a murder charge. Says she shot her boyfriend after he turned nasty when she tried to leave him."
He's going to have to ask Mary, at some point, if there's any useful crime-solving advice he could have got from going to Les Misérables. An irrelevant thought, which he bats away, as he concentrates on spotting the flaws in her plan. It's not the sort of plan he'd ever think of, of course...
"So you were going to claim Magnussen had invited you up to the penthouse and you'd gone to see him? And then he produced a gun and tried to rape you, but you killed him defending your honour." Ingenious, he has to admit. "But a bit difficult to explain to John why you'd gone to meet Magnussen in the first place."
"Not really," Mary says, her chin going up. "I was going to tell John that Magnussen was claiming he had information on you. That he’d asked me what John would do if he heard about all the things you'd got up to while you were supposed to be dead."
"That's actually quite clever." Magnussen's not the only one who understands about pressure points, it seems.
"We've all got secrets, Sherlock," Mary says, "and I'm not the only one who'd prefer John not to know the whole truth about me. Maybe you didn't do anything stupid when you were away, but that doesn't sound like you, does it?"
"What were you going to claim I'd done?" The bigger the lie, the more easily some people will fall for it. And John's pretty gullible, especially where people he loves are concerned.
"I'd say Magnussen never told me, it was all just an excuse to get me to go and see him. Because that's his idea of fun. Picking on people who can't fight back."
He's heard enough from Janine to know that’s true, that Magnussen can't resist harassing his staff, as well as everyone else.
"You wouldn't have got away with it," he tells her, but his voice doesn't sound convincing.
"I've known people get away with murder before now," Mary says, and he wonders if John ever told her about Jefferson Hope. Probably not murder on John's part, but certainly homicide.
How could he not have seen what was happening, before he got shot? He had seen it, hadn't he, but too late? Or rather smelt it. You don't wear perfume if you're breaking into a building, not if you're a professional. But you do wear it if you're trying to act like a harmless woman. John had thought of Mary automatically with the perfume, but why hadn't he seen Mary?
"How did you avoid John when you went downstairs after the shooting?" he demands.
"I didn't go back down," Mary says. "I knew there had to be a fire-escape somewhere in the penthouse and I found it. Setting off alarms didn't matter by that point; Magnussen had all the evidence he needed against me already.”
"The alarms just stopped; it all went quiet. Or maybe I couldn't hear them anymore." All he could hear had been Moriarty singing. Moriarty singing nursery rhymes about him dying. Mary's saying something and for a moment he can't hear it, because he has to delete Moriarty singing nursery rhymes first.
He shakes his head, trying to focus. "What did you say?"
"I don’t know why it took John so long to find you,” Mary repeats. “I thought he'd be right up the stairs behind you, that I had no time to explain."
"He told me afterwards he was trying to check if any of the security cameras let him see into the penthouse; he didn't want to rush up the stairs blind into an ambush."
John for once doing the sensible thing and it had almost killed Sherlock. No, he'd almost got himself killed. Thought Mary wouldn't be able to pull the trigger, thought he could just walk over and take the gun from her, take control of the situation in the way he always did. That was really why she'd shot him, wasn't it? Because no-one likes a smart-arse. His human error. She'd asked him twice where John was, and he hadn't picked that up. If he'd only realised that that was what was scaring her, not the thought of shooting someone. That he'd removed her only means of escape, cornered her.
He closes his eyes, trying to puzzle out what the right thing is to say to a cornered assassin whom you're trying to help. When he opens them again later - two hours later? - Mary is gone.
Part 2
BBC Sherlock
Rating 12: Non-explicit het
Summary: Sherlock has to come up with a new plan to sort out Magnussen. But he also has to solve the problem of John and Mary.
Many thanks to Kalypso for betaing
Sherlock's second stay in hospital is much longer: several months, in fact. That's less about the doctors' stern warnings to him about his body needing time to recover - there's only one doctor he's ever paid any attention to - and more about the need to avoid clients. Well, one client specifically. Lady Elizabeth Smallwood.
She won't come and visit him in hospital: far too conspicuous. And nor will she risk her phone calls or letters being intercepted. But shortly after he returns to Baker Street, she will doubtless slip discreetly into the flat one evening and demand a progress report. And that will be tricky, to say the least.
Sherlock's broken bad news to clients before - your new wife's run away with her real husband, your cushy job's been set up to cover for a bank robbery - but this is in a different league. I attempted to negotiate with Magnussen about your husband's letters and he pissed in my fireplace. I got into his office by false pretences, but he discovered me in the act, so that he can now link you personally to an attempted cover-up. I currently have no idea on how to access the Appledore vaults and would not be fit to do so in any event. In my professional opinion, you are royally fucked and you should do whatever Magnussen demands.
The best he can hope for at that point is Lady Smallwood taking him off the case. Even that means Sherlock loses his cover story if Mycroft or Lestrade start asking why he's still sniffing around Magnussen. Far worse is the likely consequence of the one other detail he'll have to include in his report to Lady Smallwood. When I was in Magnussen's office someone shot me. Magnussen may call Lady Smallwood an old woman, but Sherlock knows just how dangerous old women can be. Especially if they start asking awkward questions, like: Who could be gunning for Magnussen, but decide to shoot you instead?
Lestrade's being deliberately, helpfully clueless about the whole incident. Accepted Sherlock's statement that his attacker was masked, that it was all a blur and he can't remember any details about him or her. Presumably accepted whatever lies Magnussen has told in his witness statement. Lestrade will send his team off on a few wild goose chases and then let the case go cold. And why would Donovan be interested in catching someone who shot Sherlock, except to give them a medal? No problem there.
If anyone focuses properly on the case, though, they might deduce - or at least guess - that Sherlock is protecting his attacker, and that narrows down the field of suspects drastically. And Lady Smallwood, beneath her genteel facade, is both tough and sharp. If it's clear that Sherlock can't handle Magnussen, she might try to do so herself, and Sherlock doesn't need any more unexpected female interventions.
He's fairly confident though that she won't act before she's talked to him, heard exactly what he learned from Magnussen. So he needs to stay in hospital - heroically suffering the consequences of his efforts on her behalf - until he's found a solution to the problem. Then he can make a rapid recovery, and when Lady Smallwood does come calling, reassure her that the whole situation is under control.
Well, that's the theory: now he just has to fill in the details, such as being able to leave the hospital without collapsing, and the actual taking down of Magnussen. And, of course, it’s not the only situation Sherlock has to get under control. Because the other problem - perhaps even the more urgent one - is what to do about John and Mary’s estrangement.
***
John's making even more hospital visits the second time round. Probably worrying that, if he takes his eyes off Sherlock for too long, he'll abscond again. Mary's there frequently as well, presumably as some kind of atonement. It takes far too long for Sherlock's morphine-fuddled brain to realise that they're visiting him in shifts: he gets John or Mary but rarely John-and-Mary. And even longer to work out that the shifts are so that they avoid each other. That John can't bear even to say goodbye to Mary as she leaves; that Mary keeps looking at her watch during her visits not because she's bored, but because she's trying to work out how long she's got before John turns up.
Mary's still working at her old surgery; John's quit and got a job with an out-of-hours service. He's not cycling to work anymore, which is good, because he'd be a danger to himself in his current state of mental confusion. But he's lost weight, even with less exercise. He talks about old cases, especially the unsolved ones, as if that's going to help anchor Sherlock to life, encourage him to recover. Sherlock has a speech planned for the day John finally does want to talk about Mary - he's quite proud of how compassionate he sounds - but so far there's been no good opportunity to use it. John has to be allowed to brood for a while first.
Sherlock can at least drop a few hints. John's oddly relieved when he turns up one day to see that The Coat is back, as if it's a symbol for Sherlock's own eventual restoration.
"As good as new," Sherlock says. "Anthea knows a dry-cleaner who's exceptionally good at removing blood stains. She sends you her love, by the way."
For a moment a sentimental smile hovers on John's expressive face, and then it's gone.
"She probably doesn't remember who I am. We only met briefly," he says hastily. "And her name's not Anthea, anyhow."
All true, of course, but it's still worth reminding John about her. Because when John asked out Anthea, all he knew about her was that she had a fake name and was working for a man whom he believed to be a criminal mastermind. If Sherlock had been paying more attention when he first heard that story, he should have realised what John's type of woman was.
Looking back, he wonders how he ever missed the signs. John decided he wanted a second date with Sarah after she helped him fight Chinese gangsters, and wasn't the one with the nose some kind of mountain-climber? He remembers vaguely some unfortunate comment of his about whether she actually needed an ice-axe. As for the one with the spots, who would have thought a woman so afflicted would have had such a complex love-life?
There's another one he's missed, probably several, but there are some of John's ex-girlfriends so boring that John himself couldn't remember basic details about them. The overall pattern remains, however. It's not simply good looks that unite the women John falls hardest for: women with a taste for danger and ones with a mystery surrounding them are more prominent. It's why John's always good at chatting up witnesses in their cases.
Another image abruptly surfaces from his mind. Irene. John quite liked the thought of getting Irene's attention at first, didn't he? Yet another dangerous, mysterious woman. And then he remembers why Irene isn't a good example at all. She hurt Sherlock and John could never forgive her for that. What was it he'd said to her at the power station? How come I can see you, and I don’t even want to? It hadn't simply been jealousy, had it? John can forgive injuries to himself and even people lying to him; it's the only reason their friendship’s survived four and a half years. But enemy of Sherlock is an automatic red flag for John. One of the things Sherlock has to do is demonstrate to John that he doesn't have a problem with Mary. Or at least only a deductive one.
***
For the first few days Mary presumably makes the kind of banal conversation that Sherlock's brain automatically filters out. That leaves him plenty of time to contemplate getting into Appledore. Unfortunately, his first two plans both contain obvious flaws, and he can’t for the moment think of a third one. Time to distract his mind, perhaps, and leave his unconscious to solve the problem. Focus on something trivial, while waiting for inspiration. Like Mary’s knitting technique.
She’s given up talking to him by this point, and just sits by his bed and knits stuff for the baby. She is one of the more hopeless knitters that Sherlock has ever seen and he’s getting frustrated enough by it that he feels the need to explain how it should be done.
"How do you know about knitting?" she asks. "You can't have looked it up on YouTube this time."
"Mummy taught me," he replies. "She was very good. When I was thirteen, she knitted me a Möbius band scarf."
"A what?"
He explains the concept and ends up telling her quite a bit more about Mummy as the days trudge slowly past. She's a good listener, he'll give her that.
***
It’s frustrating how he’s not just tired all the time, but the drugs are also fogging his memory. He has to write things down just to organise his own thoughts, as he slowly starts to climb the mental stairs back up to where he should be. He’s not ready for Appledore, but what about Mary? If he can learn more about her, that might help him clarify what to say to John.
But he can't ask Mary questions, that's the problem. She gave John the flash drive, not him, but John clearly hasn't looked at it yet. So if Mary answers Sherlock's questions, she's giving him information that John doesn't know, which is not going to turn out well. But if he deduces things about Mary himself and then checks his deductions with her, that's OK. Probably OK. He's not brilliant at ethics at the best of times, but it sounds plausible, at least.
What he can ask Mary about, he realises after some consideration, is how she broke in that night, got into Magnussen's penthouse despite all the obstacles. It's not cheating to ask about that: John won't care how Mary did it. That's not what's nagging at his mind.
But as soon as Sherlock actually concentrates, realises what the correct question is, he knows half the answer already. The next time Mary turns up, as she's just sitting down, reaching to pull out the knitting from her bag, he says:
"You had an escape route from Magnussen's penthouse via the outside of the building, so why didn't you come in that way as well, ambush him there? Why enter through his private office and risk being spotted?"
Mary straightens up, and she doesn't have the knitting needles in her hands. Which is just as well, because if you're a trained assassin, you can probably do someone a nasty injury with them. She just looks at him, with that set air to her face that reminds him she is capable of much more violence than most people he knows. But also, perhaps, of showing much more courage.
"And how does someone get past every level of security known to man and into that office?" Sherlock goes on. "By being invited through, like I was. But Janine didn't expect you that night. So who else would have let you waltz up to the top of the building?"
"Sherlock-" she begins, but she doesn't need to tell him the next bit, because he's already deduced it.
"Magnussen wanted to harass you, didn't he, so he invited you up to his penthouse?"
Her hand moves instinctively towards her phone, as if she's remembering that particular message. As if she has to check, even now, that it's been deleted.
"He said he'd had a little chat with you and John," she replies. "I thought...I thought for a moment he'd already told you what I was."
"But he didn't know you were an assassin, surely? Or he’d only have dared meet you in a public place." Or at least in a building with your picture plastered all over it. Even a brilliant man needs to take some precautions.
"He knew Mary Morstan was dead," Mary says slowly. "That was his first message to me. Two weeks after I got engaged."
"What did it say exactly?" he asks, because strictly speaking he's still working on her case and it might help. And he knows she has an excellent memory.
"So sorry about the tragic end of Mary Morstan. Her friends will be devastated. C. A. Magnussen."
"That was the easiest thing to spot, for anyone who was looking," he says, knowing he should have picked it up. "Even orphans have someone around from long ago. A beloved aunt; a friend who helped look after them."
Mary nods. "Magnussen didn't mention any other deaths. And I wasn't gonna sit around and wait while he found where the bodies were buried."
It's hard to plan a murder as well as a wedding, isn't it? She'd been very efficient, making friends with Janine so quickly, but she hadn't been able to use that information. Until Magnussen finally gave her her chance.
"He doesn't expect his victims to fight back," Sherlock says. "Especially the women. That's why he liked the thought of inviting you after he'd just humiliated us. No problem in getting through the outer levels of security. But even so, they must still have checked you before letting you into the building."
He forces his mind back to that image of Mary turning to look at him that night. Don't look at the gun or her face. Dressed all in black, including black hat and gloves. Nothing too unusual there. Body armour and assault vest - bit of a giveaway. "How did you get your equipment past?"
"I had a coat on and I made sure I was looking pretty pregnant. They didn't bother searching me thoroughly, once I'd gone through the metal detector."
"And the gun?"
"I didn't take one. I knew some of the security guards were armed, so I’d be able to steal a weapon.”
Mary's voice now is calm, professional. She's been trained to make rapid decisions, hasn't she? And to fight dirty if necessary. "It was easier than I expected to start with, despite Janine saying the security was ridiculously tight. She'd told me there was another lift - for plebs - up to the top floor, as well as Magnussen's private one. I thought she meant they both went right up to the penthouse. I had an armed guard escorting me and I guessed there'd be a security camera in the lift. But I doubled up as I was coming out of it, like my stomach was hurting me. I'm short, blonde and pregnant; he didn't expect me to attack him."
Her left elbow twitches slightly, and Sherlock is abruptly reminded of Irene smoothly disarming a gunman. He nods. Also explains why the unconscious guard was up on the 32nd floor, not the 31st, where they were normally based.
"But then you realised you'd come out into his office, instead of the penthouse?" Mary had been expecting privacy, but she hadn't understood that Magnussen didn't care what his underlings saw. "And you saw Janine?"
"That was close," she says. "Magnussen must have worked out Janine and me were friends and wanted her to watch me go up to his flat. Because then she'd know he had some dirt on me, and I'd know she knew that. He liked making women suffer."
He can hear the tension in her voice now. Grit in the killing machine; the personal involvement that had distorted her professional judgement.
"Janine was double-checking to make sure that Magnussen was going to stay out of the way for some time," Sherlock comments. "She didn't look round till it was too late."
"I didn't have a choice by that point," Mary says bleakly. "And I'm fast. I have to be. I've always had to be fast and good."
"Good enough to shoot my liver, thus avoiding major arteries, but not to miss the inferior vena cava. You didn't want to kill me, but you knew there was a risk, didn't you?"
Mary shrugs, as if she can't explain her decision exactly even to herself. How much does your training take over automatically in such a stressful situation, Sherlock wonders, as he starts to replay the key moments in his mind. Probably some time since her last hit, but she'd have been trained to kill, not wound, wouldn't she? She could have shot him through the heart and he'd never have left that room. Or his leg, and he'd never have walked properly again. Or his hand and no more violin playing. Easy to say she made a fatal mistake, harder to know what she should have done. What he would have done if he was her? Well, not shot anyone, obviously. Not even sprained anyone.
He thinks he didn't say that last bit out loud. But Mary's presumably been carrying on their conversation - her mouth's open and there's a determined look on her face - so he tunes in to her again.
"I had to shut you up," Mary says, "and you never shut up. Why didn't you let me kill Magnussen?"
"I couldn't-" he begins.
"-or let Lady Smallwood, or whoever you thought I was?"
As if it's his fault that her murder plan was unworkable. Maybe she needs to be reminded of that.
"Did you think you could possibly get away with it?" he announces, and abruptly realises that it's far harder sounding effortlessly superior when you're lying down semi-naked with a drip in your arm. "Your face was uncovered. You'd been seen going into the building, you'd have been seen going out again."
And then his mind catches up with his own words. "Oh, I see. You weren't going to leave, were you? You were going to kill Magnussen and then kill yourself."
There's a snort from Mary, as if she's in pain; but when he focuses, he realises that she's laughing. Even if she does look as if she's about to cry as well.
"Don't be bloody stupid, Sherlock," she says, at last. "I play to win. You don't like musicals, do you? Shame, because Chicago's really good. There's a song in it called 'We Both Reached for the Gun', where a woman talks her way out of a murder charge. Says she shot her boyfriend after he turned nasty when she tried to leave him."
He's going to have to ask Mary, at some point, if there's any useful crime-solving advice he could have got from going to Les Misérables. An irrelevant thought, which he bats away, as he concentrates on spotting the flaws in her plan. It's not the sort of plan he'd ever think of, of course...
"So you were going to claim Magnussen had invited you up to the penthouse and you'd gone to see him? And then he produced a gun and tried to rape you, but you killed him defending your honour." Ingenious, he has to admit. "But a bit difficult to explain to John why you'd gone to meet Magnussen in the first place."
"Not really," Mary says, her chin going up. "I was going to tell John that Magnussen was claiming he had information on you. That he’d asked me what John would do if he heard about all the things you'd got up to while you were supposed to be dead."
"That's actually quite clever." Magnussen's not the only one who understands about pressure points, it seems.
"We've all got secrets, Sherlock," Mary says, "and I'm not the only one who'd prefer John not to know the whole truth about me. Maybe you didn't do anything stupid when you were away, but that doesn't sound like you, does it?"
"What were you going to claim I'd done?" The bigger the lie, the more easily some people will fall for it. And John's pretty gullible, especially where people he loves are concerned.
"I'd say Magnussen never told me, it was all just an excuse to get me to go and see him. Because that's his idea of fun. Picking on people who can't fight back."
He's heard enough from Janine to know that’s true, that Magnussen can't resist harassing his staff, as well as everyone else.
"You wouldn't have got away with it," he tells her, but his voice doesn't sound convincing.
"I've known people get away with murder before now," Mary says, and he wonders if John ever told her about Jefferson Hope. Probably not murder on John's part, but certainly homicide.
How could he not have seen what was happening, before he got shot? He had seen it, hadn't he, but too late? Or rather smelt it. You don't wear perfume if you're breaking into a building, not if you're a professional. But you do wear it if you're trying to act like a harmless woman. John had thought of Mary automatically with the perfume, but why hadn't he seen Mary?
"How did you avoid John when you went downstairs after the shooting?" he demands.
"I didn't go back down," Mary says. "I knew there had to be a fire-escape somewhere in the penthouse and I found it. Setting off alarms didn't matter by that point; Magnussen had all the evidence he needed against me already.”
"The alarms just stopped; it all went quiet. Or maybe I couldn't hear them anymore." All he could hear had been Moriarty singing. Moriarty singing nursery rhymes about him dying. Mary's saying something and for a moment he can't hear it, because he has to delete Moriarty singing nursery rhymes first.
He shakes his head, trying to focus. "What did you say?"
"I don’t know why it took John so long to find you,” Mary repeats. “I thought he'd be right up the stairs behind you, that I had no time to explain."
"He told me afterwards he was trying to check if any of the security cameras let him see into the penthouse; he didn't want to rush up the stairs blind into an ambush."
John for once doing the sensible thing and it had almost killed Sherlock. No, he'd almost got himself killed. Thought Mary wouldn't be able to pull the trigger, thought he could just walk over and take the gun from her, take control of the situation in the way he always did. That was really why she'd shot him, wasn't it? Because no-one likes a smart-arse. His human error. She'd asked him twice where John was, and he hadn't picked that up. If he'd only realised that that was what was scaring her, not the thought of shooting someone. That he'd removed her only means of escape, cornered her.
He closes his eyes, trying to puzzle out what the right thing is to say to a cornered assassin whom you're trying to help. When he opens them again later - two hours later? - Mary is gone.
Part 2