Act I
Top pop music composer Vernon Gersch, hoping to find a new collaborator, meets offbeat Sonia Walsk, who has already had some success writing lyrics and is in awe of his accomplishments, at his luxury Manhattan apartment. She is surprised that his Oscar is so light, and Vernon quips, "They're chocolate inside." He is aloof and focused, while she is disorganized and distracted, but Vernon has already written music to one of Sonia's lyrics, and they decide to forge ahead. Sonia, frazzled by her break up with lover Leon, arrives a day late for their first work session. When they begin, she tells Vernon they should get to know each other on a personal level in order for their work to gel, and they decide to have dinner at "Le Club."
Sonia, who has been trying to ease Leon's anguish, is late yet again, and the evening begins badly. She and Vernon argue, then dance in an effort to calm down. The two settle down to enjoy the evening, and they hear their own songs being played over the sound system. Another work session, in which the two really don't listen to each other, follows, but Vernon convinces Sonia to join him for a romantic weekend at a Long Island beach house. The trip to the island in Vernon's small sports car is fraught with engine trouble, calls to Leon, and arguments. They finally arrive at the house, but a phone call from Leon threatens the romantic mood. Determined to concentrate on Vernon, Sonia tells Leon that she can't help him and hangs up.
Act II
It's a week later and Vernon is suffering from insomnia. Sonia manipulates her way into his apartment by telling him she has no place to stay since Leon is back living at her place. Sonia and Vernon's romance and collaboration seems successful for a while, but the relationship begins to crumble because of her inability to send her ex-boyfriend away. Also, away from his piano, Vernon is a bundle of neuroses and unable to express his deepest feelings. After some psychologizing about the difficulties of living and working together, the pair split up at a recording session.
A few months later, while Vernon is in a Los Angeles hospital, Sonia arrives unexpectedly with a tiny red child's piano as a get-well gift. Months later, both have separately come to the realization that, despite their differences, they are better together. Vernon arrives at Sonia's apartment in New York to tell her that he wants to try again. She agrees, and they reconcile with a kiss.