After a car accident in 2006, Sam Tyler wakes 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?

When Sam responds to a fatal stabbing at Crester's Textiles he's shocked to discover that it's the converted mill where he lives in 2006. Sam sets up a forensic investigation but Gene already has a hunch about the murderer. Sam believes he has to stop Gene from sending an innocent man down for life. But does he have more to learn about this world than he thinks?

Gene believes that local gangster Stephen Warren and the police can co-exist and that the streets are safer as a result. But Sam knows that in the future, dodgy deals like this will irrevocably change the relationship between the public and the police. Whilst Gene lays a ghost to rest, Sam sets to work on convincing his new partner, but is distracted when he meets his mother as a young woman.

Sam and Gene go undercover in a local pub to solve the murder of a local Manchester United fan. As Gene looks like he's set to drink the pub dry, Sam worries about their chances of finding the killer before Saturday's big match. With the press using the murder to fuel the flames of hate between rival fans, Sam is under pressure to solve the murder before the tensions destroy the community.

When his mother's voice bleeds through from 2006 and he hears her say goodbye to him, Sam is desperate - he's alive and determined to make himself heard. But then the call comes in that a man has taken people hostage at the Manchester Gazette and is intent on killing them at 2pm - the same time Sam's machine will be switched off. Could stopping the hostage-taker be a way of staying alive?

Sam demands a transparent investigation into the death-in-custody of small-time drug dealer Billy Kemble. He believes that if the police don't police themselves, the public will never trust them. When the explosive evidence of what happened to Billy falls into his hands, Sam has a huge decision to make. This evidence could tear the team apart. It's an opportunity to destroy his world and the people in it, but also perhaps an opportunity to get home.

Sam is finally accepting of this world - until he comes face to face with his 29 year-old dad, Vic. Vic Tyler is a small time gambler who unwittingly finds himself at the centre of a murder enquiry. As Sam moves to protect his father, he embarks upon an emotional journey, piecing together a childhood memory and uncovering an uncomfortable truth that will change him forever.

Tyler has visions of someone disrupting his life support system in 2006, and encounters who he thinks is the same assailant in 1973, running a gambling syndicate and protection racket. Recognising the man as a killer he failed to stop in the future, Tyler is prepared to go to any lengths to make sure his life is not threatened and the man doesn't kill his original victim.

After collecting a career safe breaker from prison for further questioning, Tyler, Ray and Chris are attacked by armed men enabling the escape of the prisoner. Is a local gangster to blame, or was the crime actually arranged by Gene's old mentor? Meanwhile, Sam tries to discourage the first black detective in the department from doing an Uncle Tom act, as he will become Sam's mentor when he first joins the force.

The team receives a warning, claiming the IRA has planted a car bomb in Manchester. Sam realises the warning doesn't conform to IRA techniques. However, when Sam's knowledge backfires, nearly killing Ray, the department shuns his line of investigation to focus on an Irish socialist group. Meanwhile, Sam's visions of the future suggest he may have suffered brain damage, affecting his higher reasoning, due to him being in a coma for so long.

The body of a young woman is found on wasteland. The investigation takes the team to suburbia, where a local car dealer is throwing private parties, employing make-up girls from a local company to “help out” when the wife-swapping begins. Posing as married couple Tony and Cherie Blair, Sam and Annie infiltrate one of the parties, only to discover that it isn't as simple as they think.

The team investigates the abduction of a young woman and her daughter, who are being held prisoner by somebody who wishes the team to release a prisoner arrested on a murder charge a year ago. At the same time, Sam faces a life or death situation in 2006 when he thinks he has accidentally been given an overdose. As the deadline draws closer, Sam collapses into a deeper coma, leaving his colleagues to tackle the mystery on their own - albeit using some of his earlier suggestions.

As heroin hits the streets of Manchester for the first time, CID and DCI Hunt want culprits for the smuggling, the dealing and ensuing violence, which becomes difficult when Annie is kidnapped by the smugglers. As Sam tries to get to the source of the influx of this deadly drug, he finds himself intractably drawn to a beautiful young woman who was witness to a heroin-related shooting - and who, he later realises, is the future mother of his 2006 girlfriend. At the same time, Sam's 'visions' reveal that his girlfriend has decided to stop visiting him in hospital, as she can't keep waiting for him to wake up.

A water-tight court case fails to put away a local gangster. Unable to cope with a guilty man walking free, DCI Hunt turns to alcohol but soon finds himself in a spot of bother. When it appears as though Hunt may have killed someone, it's up to Sam, torn between Gene and his replacement - a DCI who actually uses Sam's modern police techniques and vocabulary - to help him out.

Sam learns that an operation is to be conducted upon him in 2006 to try and revive him from his coma. However, he believes that to return to the 21st century, he has to betray his colleagues in 1973 - but can he regard them as real or imaginary?