Hey there! I just got the series on DVD...virgin megastore in London (I think you can order online).
So I'm watching and in "The Origin Story" (a.k.a. the pilot episode) we meet Lisa. She's nowhere to be found but never had a parting scene or a passing explanation. In Culex we meet Amy, but she doesn't appear in "Living Stones". We meet another girl whose name escapes me in Culex, but we don't see her again until "Living Stones", where she 'knows the ropes'; there's no "First teleportation, what's happening to me, there's an alien spaceship" scene with her...
Can someone fill in the blanks for me?