The story revolves around the murder of a young woman and the subsequent investigation by hard-boiled detective, Lieutenant Sam Carson. As Carson delves deeper into the case, he uncovers a web of corruption and deceit that leads him to the heart of the city's political machine. Along the way, he encounters a beautiful nightclub singer who becomes a key player in the unfolding drama. The film is notable for its moody atmosphere, complex plot, and strong performances by the cast, including Carole Landis as the singer and William Gargan as Carson. Overall, "Behind Green Lights" is a classic example of the film noir genre, and a must-see for fans of hard-boiled detective stories.