Middle-aged seafood restaurateur Barney Cashman (Alan Arkin) is a man with a mission - to have one great extramarital affair to make his humdrum life complete. And with his mother's apartment vacant one day each week, he has the perfect lair - now all he needs is the perfect partner. That's when Barney discovers that being a great Don Juan is much more complicated than he ever imagined! His hilarious attempts at seduction net him an unemotional, jaded sexpot (Sally Kellerman), a struggling starlet (Paula Taylor) who, in reality suffers from an intense state of melnacholia.