The Doctor, Rose and Adam travel 200,000 years into the future and land on Satellite 5, a space station orbiting the Earth. From the moment they arrive, the Doctor feels that something is wrong but he can't quite put his finger on it. Satellite 5 provides 600 channels of news and information to everyone on Earth and the crew, all humans, have a chip implanted in them allowing their brains to work as computers. As they explore the station, the travelers learn of the mysterious Level 500 that... some of them are promoted to but are never seen again. The Doctor and Rose go to that mysterious lev el to find out just who - or what - is up there. Adam meanwhile tries to access the computer banks with the view to taking advanced knowledge back to present day Earth.