Sandra Carpenter (Lucille Ball) is a London-based dancer who is distraught to learn that her friend has disappeared. Soon after the disappearance, she's approached by Harley Temple (Charles Coburn), a police investigator who believes her friend has been murdered by a serial killer who uses personal ads to find his victims. Temple hatches a plan to catch the killer using Sandra as bait, and Sandra agrees to help. But complications arise when Sandra becomes engaged to a nightclub owner.