Three lifelong pals embark on a chaotic quest to solve the mystery of their old friend's suspicious death and keep their own dark secret under wraps.

Janet is a foul-mouthed, hilarious, Belfast supermarket worker who doesn’t care about anything, including her life. Seamus is a handsome, self-centered, political broadcaster with what looks to be a perfect London life and a celebrity girlfriend. When they unexpectedly meet, they instantly clash – and yet also find themselves inextricably drawn to each other.

A probation officer, Cathy Madden, is tasked with rehabilitating a notorious killer named 'Bloody' Mary Laidlaw back into society following a two-decade sentence.