Captain Jack Harkness is the leader of Tourchwood, and he is in love with Gwen Cooper. But when Gwen and her husband Rhys tell him she's pregnant, he gets over her.
When her daughter, Alexandra (Alex / Lexi) is born, she grows up into a wierd life of strange parents and alien fighing. When she is 13, she goes to California to go to boarding school, leaving everyone behind in england. But when she is 17, she is kicked out of school, for street racing, street fightng, and being a badass in school. When she gets back she's completely changed from the sweet, innocent girl she was when she left. She joins Jack and her parents with alien fighting, and Jack cant help but find himself drawn to her.