The Doctor, Rose and Adam arrive in the year 200,000 aboard a space station above Earth supposedly during the Fourth Great and Bountiful Earth  Empire.  It is soon learned that things are not going along the lines that they should.  The Doctor and Rose attempt to make it to floor 500 to investigate while Adam has other plans.  Adam gets an implant in his brain so that he can access data that would give him information when he arrives back in his own time.  He uses Rose's cell phone to send this information to his answering machine at his parent's home in his own time.  Meanwhile, the Doctor and Rose are held captive by the Editor and the Jagrafess (the mastermind of the station's workings).  With the help of Cathica, they heat up the station and cause the Jagrafess to die.  The Doctor, having learned what Adam has done, returns him to his parent's house and destroys the information on the answering machine.  He dooms him to an existence where he must keep his implant a secret or else...