An irrepressible cad by nature, Michael James (Peter O'Toole) is determined to reform and stay faithful to his fiancée, Carole (Romy Schneider). However, Michael's attempt at fidelity is jeopardized when numerous attractive women become smitten with him, including Liz (Paula Prentiss) and Rita (Ursula Andress). Meanwhile, another of Michael's admirers, Renée (Capucine), is the object of fixation for his therapist, the wacky Dr. Fritz Fassbender (Peter Sellers).