I'll be doing a canon update for Martha this week, thanks to a convenient TARDIS accident. After the update, she'll be taken from the end of the last S4 episode, "Journey's End".
Key events for Martha after S3:
- She's now a fully qualified medical doctor.
-
UNIT offered her a job, based on the Doctor's recommendation, and she accepted. (Which means
this is now canon for Martha on Island.)
- At some point, she contacted
Thomas Milligan again and they began dating. Later they got engaged.
- She kept in contact with Jack Harkness, and visited Torchwood 3 in her capacity as a UNIT officer to investigate several strange deaths. (Met Ianto Jones, Gwen Cooper, Toshiko Sato, and Owen Harper.)
- She served as Medical Officer for Torchwood 3 for a short period of time while Owen Harper was temporarily relieved of duty.
- When UNIT began investigating ATMOS, Martha called the enhanced mobile phone she'd left with the Doctor and requested his help. (Met Donna Noble at this time.)
- After the defeat of the Sontarans, she was accidentally taken along on the TARDIS to Messaline, meeting Jenny (the Doctor's daughter).
- UNIT promoted her to Medical Director of
Project Indigo.
- When Earth was transported to the Medusa Cascade by the Daleks, Martha escaped UNIT's New York HQ by using Project Indigo. She later attempted to force the Daleks to return Earth by threatening to use the
Osterhagen Key. The Daleks transported her to their ship to prevent her from using it.
- She was part of the "Children of Time" group that helped the Doctor fly the Earth back home using the TARDIS. (Finally met Rose Tyler, as well as Jackie Tyler, Mickey Smith, Sarah Jane Smith, and the 'half-human' Doctor.)