Benny runs the Soho nightclubs "The Ace of Clubs" for the owner, Rita. Felix, the compère, introduces the club's girls, who perform their opening number. Benny plans the pickup of a parcel with a gangster, Smiling Snyder. The parcel is in the cloakroom wrapped in a raincoat. When Snyder forcibly steals a kiss from Pinkie Leroy, the club's star, in the middle of her act, a sailor named Harry punches Snyder, who draws his gun and fires. Pinkie takes the raincoat to cover her skimpy costume and escapes with Harry.
Harry and Pinkie discover the parcel in the raincoat, but it falls out and Harry finds it after Pinkie goes back to the club. Benny is already looking for the missing parcel, and Rita, who is in love with him, realises that Benny is involved with the gangsters. At rehearsal the next afternoon, Harry comes by to see Pinkie. Detective-lnspector Warrilove arrives to investigate a jewel robbery and shooting. He suspects Snyder. Benny discourages Pinkie from becoming involved with Harry. That evening Snyder and his associate, Guy, kidnap Harry during the show, but he escapes. Pinkie, afraid for Harry's safety, promises Benny that she will get the parcel. Harry is hidden, and after Benny leaves, he and Pinkie meet.
The next day, Harry return with the parcel, suggesting that they give it to the police. Pinkie disagrees, and they argue. That evening, one of the girls mistakes the parcel for her birthday present and opens it, finding the purloined necklace. Snyder and Gus pick up the parcel in exchange for cash. Rita hears that the stolen necklace has been traced to the club. She asks the gangsters to leave. In the club, Warrilove notices the necklace, which the birthday girl is wearing, and he follows her. Snyder and Gus open the parcel to find the birthday present, a pair of falsies. They return to the club, and Worrilove catches them. All ends happily for Benny and Rita as well as Pinkie and Harry.