Hoping to update his chapter on modern slang, encyclopedia writer Professor Bertram Potts (Gary Cooper) ventures into a chic nightclub. Inside, he meets the snarky burlesque performer "Sugarpuss" O'Shea (Barbara Stanwyck). Fascinated by her command of popular jargon, Potts invites her to stay with him. But, unknown to Potts, she is the fiancée of a mobster (Dana Andrews) and wanted by the police. In the ensuing mayhem, Potts must stay on his toes or be swallowed up by bigger fish.