Dean Martin is Dino, a Las Vegas crooner, alcoholic, and celebrity playboy. Dino requires women like oxygen — a companionless night leaves him with a headache. Ray Walston is Orville, a provincial piano teacher, aspiring songwriter, and jealous husband. Orville violently obsesses over his wife Zelda's fidelity — any man she encounters becomes his sworn enemy. When a chance detour brings Dino to Orville's hometown of Climax, NV, it is the perfect opportunity for the piano teacher and his songwriting partner Barney to pitch their tunes. Yet, Orville predictably fears the possible combination of Dino's libido with Zelda's childhood crush on the singer. Before the two can meet, Orville deceitfully bullies Zelda out of their house and Barney hires local roadhouse prostitute Polly the Pistol (Kim Novak) to pose as Orville's wife. Zelda turns to drink for solace, ending up at the exact bar where Polly plies her trade and, eventually, in the call girl's empty trailer. By the next morning, Orville is with Polly and Dino (looking for a prostitute) finds his way to Zelda — and husband, wife, hooker, and Barney will all reap the benefits of infidelity.