One main sexual complication is at the heart of Stay as You Are. Guillo (Marcello Mastroianni) is a successful middle-aged landscape architect who is unhappily married. For diversion he turns to the foxy charms of Francesca (Natassia Kinski), a nubile teenager who throws herself at him. But as their affair slowly begins to blossom, he learns that she may be the daughter of one of his former flames. The inference of incest draws out Guillo's innate fear and insecurities. Director Albert Lattuada focuses on his resultant hesitations, his uneasiness in the presence of both wife and daughter. These scenes are quite affecting. A humorous aspect of the drama is conveyed by Francesca's father complex which is evident in the posters of Lenin, Hemingway, Einstein, and Churchill which paper her apartment. The surprising finale leaves Guillo the victim of his own womanizing.