Prominent criminal attorney Amos Strickland (Nicholas Joy) checks into the Lost Caverns Resort Hotel, and is later discovered murdered by the bellboy, Freddie Phillips (Lou Costello), who is implicated in the crime. Casey Edwards (Bud Abbott), the house detective, tries to clear Freddie, but Inspector Wellman (James Flavin) and Sergeant Stone (Mikel Conrad) keep him in custody. Seven of Strickland's former clients happen to be at the resort, and they are all suspects. These former clients are Swami Talpur (Boris Karloff), Angela Gordon (Lénore Aubert), Mrs. Hargreave (Victoria Horne), T. Hanley Brooks (Roland Winters), Lawrence Crandall (Harry Hayden), Mrs. Grimsby (Claire DuBrey) and Mike Relia (Vincent Renno). They gather for a meeting, and decide that they must conceal their pasts and that Freddie must take the blame for Strickland's murder. They try unsuccessfully to get Freddie to sign a confession, e.g., Angela tries to seduce him, but the police stop her when they fear she's poisoned the champagne. Then the Swami attempts to hypnotize him into committing suicide, but his stupidity saves him.