Okay, so, not the Jack she knew. "I don't think," Martha said carefully, giving into temptation and taking a chip, "we know the same Jack Harkness."
Although stopping people destroying the world, yeah, that sounded pretty like Jack, but keeping one guy from doing it as a full time thing? "My Jack - well, okay, he's not my Jack, not really, but the Jack I know? - he heads up Torchwood in Cardiff. I think he said Three?"