
Every Thursday, the group gathers not for an illicit act like murder, but rather to scrutinize intricate details of cold, unsolved cases. The first case they tackle is about a woman who fell from a window with a knife in her back. However, their investigation skills are swiftly directed towards their own premises when the property developer, Ian Ventham (played by the charismatic David Tennant), who owns the grounds of their retirement home, and his building contractor are found murdered. Despite the local police led by a typical inept inspector (Daniel Mays), they decide to step in and solve it themselves, drawing the inspector’s female assistant (Naomi Ackie) into their efforts as well. The investigation uncovers a Pandora’s box filled with fugitives wanted for years, secret graves, and human trafficking as the film builds towards its climax and the ultimate revelation.