Tempermental torch singer Gail Preston performs at the Swing Swing Club, a ritzy nightclub decorated in a prison theme, at which patrons have the choice of sitting in cells that line the room or at tables. Gail is not well-liked by her co-workers, so when she is murdered one night during a performance, Inspector Kellogg and his hapless assistant, Cliff Connolly, are faced with many suspects. The first suspect is Mr. Owen, who commits suicide by jumping off a tall building. Next, orchestra leader Swing Traynor is arrested, despite the best efforts of Ann Bishop, who is secretly married to Traynor, to prevent it. A break in the case finally comes when Kellogg discovers that the murder was committed by someone who attached a gun to one of the nightclub spotlights. To determine the murderer, Kellogg convenes all those present at the club on the night of Gail's murder and, one by one, shines the spotlight on them until the killer confesses out of terror of being killed in the same manner as Gail.