Her role in the show was sadly brief, and with precious little known about the capital's division of Torchwood before the Battle of Canary Wharf, could there be scope for future exploration of Ms. Hartman's backstory?
Earlier this week the soaps team caught up with actress Tracy Ann Oberman, formerly of EastEnders, to chat about a possible return to Albert Square (you can read the interview in all its glory here). Of more interest for us, though, she was also quizzed briefly on reprising her Who role.
Do you think you'll ever go back to Doctor Who?
"Well you never know… Anything's possible in those parallel universes. Yvonne Hartman was head of Torchwood London and those two episodes introduced that show. Maybe one day they could do a flashback sequence as to how Torchwood came about."
And it would have to be flashback, wouldn't it?
"She could go back in some capacity, but yes, she did become a Cyberperson. Someone was tweeting one of the writers James [Moran] about that, but I'm just really pleased that I got to play the character in what were two seminal episodes in Doctor Who."
Have you ever been asked back?
"No, but every time I see Russell [T Davies] he says 'oh, Yvonne was a great character!' They could get Meryl Streep now if they wanted! They could have anyone."
So what do we think? Is there appetite for some Torchwood London backstory episodes? Maybe even a full-blown spinoff series?! Add your comments to this entry below!
Additional reporting by Kris Green