After Sarah Jane starts acting suspiciously, Luke, Clyde, Rani and K9 investigate. They discover she has a boyfriend, Peter Dalton, and they are going to get married. Clyde suspects Peter may be an alien. At the wedding, an old enemy returns. As the gang find themselves trapped in a time loop in Limbo, can a very special friend from the past save Sarah Jane, her friends and the entire planet Earth from the wrath of the Trickster?