Callum ‘Cal’ Rennie, a 25-year-old with dreams of musical stardom, finds solace from his monotonous day job in the vibrant world of pub band performances. However, his life takes a dramatic turn when he tragically drowns in a frozen lake trying to save a boy, only to awaken in 1964 within the body of Calvin, a deceased rent boy with a history of abuse and a mysterious death.

After a dangerous encounter with the notorious Gemmell gang in Glasgow, Callum is forced to flee to London, seeking a fresh start away from the shadows of Calvin’s troubled past. Life in the swinging sixties, however, is far from glamorous, leaving Callum to navigate a series of unfulfilling jobs until an opportunity arises to join an underachieving R&B band. Leveraging his exceptional songwriting abilities, Callum propels the band to stardom, bringing him the recognition and success he had long yearned for.

Just as Callum begins to relish his new-found fame and the joys of the 1960s music scene, the dark secrets of Calvin’s life come to light, threatening to unravel everything. The arrival of the Gemmells in London, bent on exacting retribution, forces Callum to confront the grim realities of his borrowed existence, blurring the lines between past and present, redemption and revenge.