For those who don't know, The Famous Jett Jackson was an early Disney channel show about a boy who was a TV actor in an action/spy show. At one point, though, he goes through a portal on set (supposed to be fake, actually real), and swaps his real self with his actor's personality (so now spy version of him is in the world where he's just a TV character, and the actor version ends up in the real spy scene. Eventually he fixes things, yada yada. Overall it wasn't a half bad show.
