Paige first appears in episode 1 since it's showing some scenes that happen later on in the series, but then she doesn't return till the end of season 2. She is a very important character all the way through season 3 and 4. Paige is actually a computer program, or like robot human. Let's just call her a cyborg. She was created by another character named Lauren who also doesn't come into the series for quite a while. You are just pure evil and will do anything Lauren asks you to do. You can live forever unless someone shuts your system down and of course, your highly intelligent.