In 2006, Manchester Detective Chief Inspector Sam Tyler investigates a serial killer who has just kidnapped his girlfriend and fellow officer, Maya. Following Maya’s abduction, Sam is struck by a car. When he regains consciousness, the bustling modern streets of Manchester have inexplicably vanished. He finds himself in the exact same location, but the year is 1973. Disoriented, grimy, and surrounded by flares, sideburns, and Ford Cortinas, Sam is thrust into a world stripped of modern forensic science, where
political correctness does not exist, and police brutality is normalized.Assigned to the CID branch at Greater Manchester Police, Sam is forced to work under Detective Chief Inspector Gene Hunt, a hard-drinking, rule-breaking throwback whose bullish instincts clash violently with Sam's modern, psychological approach to policing. Sam’s primary motivation is to figure out if he is mad, in a coma, or genuinely time-travelling. He desperately tries to maintain his grip on sanity by holding onto fragments of his 2006 life, which occasionally bleed through via testcard broadcasts on televisions and voices echoing from his hospital life.Throughout the series, Sam and Gene engage in a constant ideological turf war. Gene represents the brutal, gut-feeling policing of the 1970s, while Sam advocates for empathy, profiling, and adherence to the law. Despite their bitter clashes, a profound mutual respect develops between them. Sam also navigates complex workplace dynamics with Detective Constable Annie Cartwright, a perceptive officer whose intellect is constantly undermined by her male peers, and Detective Sergeants Ray Carling and Chris Skelton, whose casual prejudices challenge Sam's modern sensibilities.As Sam investigates various cases week by week, he begins to see parallels between his current investigations and his modern life in 2006. He starts to wonder if solving the crimes of 1973 will provide the key to unlocking his awakening. He frequently hears a mysterious doctor urging him to wake up, heightening his internal crisis.In the dramatic climax, Sam receives a definitive broadcast from 2006 stating that his life support is about to be switched off. Faced with a choice, Sam realizes that his heart truly lies in the messy, vibrant world of 1973 with his colleagues. In a surreal and emotionally charged finale, Sam leaps from the roof of the police station. Instead of waking up in 2006, he lands squarely back in 1973, interrupting a
retirement party. He walks back into the CID office, welcomed home by a cheering Gene Hunt, finally embracing his destiny among the smoke, grit, and brotherhood of the past.