Human Traffic ★★★★

After finally killing The Doctor, The Master has no meaning in life. So he comes to Earth, wipes his own memory and changes his name to Jip. He then befriends Danny Dyer. Jip then realizes he has no meaning in his life so he runs for Prime Minister and wins under his real name, Harold Saxon. When The Doctor returns to Earth with Captain Jack Harkness and Martha Jones, Saxon remembers exactly who he really is and history repeats itself.