After a car accident in 2006, Sam Tyler was up in 1973. Sam's 21st Century attitudes make him a fish out of water in this world of clunky technology and old fashioned policing. And nothing seems more alien than his new boss, DCI Gene Hunt, who believes in gut instinct and, all too often, sheer brute force. Then Sam discovers a connection between a murder in 1973 and the kidnapper in 2006. Could solving this case be the key to getting home?

Sam decides he has to embrace this world - for now. But then he discovers Gene is planning to plant evidence to secure the conviction of Kim Trent, an elusive criminal. Shocked by Gene's attitude to crime-solving, Sam releases Trent. But when a young woman gets caught in the crossfire as a result of Trent being freed, Sam is forced to question his methods. Can he and Gene put aside their differences and find the evidence to nail Trent?