John Simm is Sam Tyler, a police officer from 2006, who is in the middle of a kidnapping investigation involving his girlfriend when he's run over and knocked into a coma. He wakes up in 1973, a world ruled by local gangsters and football yobs. A world where there's still black and white television sets, and where sexism against women is still socially acceptable. Sam quickly realises that something is wrong, and is determined to get home, but things are never that easy. Just as Sam is adjusting to his new life trapped in the past he begins to hear the voices: his own Mum crying out to him, doctors telling him to stay calm, and relax. Worst of all is the test card girl, who comes at night warning Sam... Is Sam simply trapped in a coma like all the signs are telling him? Is he dreaming it all? Is he really from 1973, just dreaming that he's from 2006? Or is he just plain mad...?