The series delves into the pursuit of a murderer responsible for the deaths of three young women in Port Talbot in 1973, highlighting the extraordinary resolution of the case nearly 30 years later through groundbreaking DNA technology. It contrasts the investigative techniques of the 1970s with the forensic advancements of the early 2000s, depicting a community grappling with the impact of an unresolved crime decades later, and questioning whether true justice can ever be achieved.