Two young singles meet at a bar, sleep together, and spend the next day getting to know each other.

John, a furniture designer, and Mary, an art gallery assistant, meet at Maxwell's Plum, a New York City singles bar. Without exchanging names, they go back to John's fashionable Riverside Drive apartment and make love. Mary awakens, and while John sleeps, she looks through his book collection, at his furniture, and at a picture of his former girl friend, Ruth, a model. While Mary showers, John gets up and examines her handbag to find out who she is. Unenthusiastically, he makes breakfast for her. They engage in casual conversation while each privately sizes up the motivations of the other and recalls recent unhappy affairs. After breakfast, John plays a recording of Handel's music on his stereo system and exchanges verbal attacks with Mary. Their thoughts continue: John recalls the time that Ruth came uninvited to his apartment with all her belongings, and Mary thinks of her recent affair with James, a married politician. Mary leaves the apartment, but she forgets her keys and returns. John makes lunch for her, and during the afternoon she goes to sleep on his bed and dreams of a date with the politician in a hotel room. When she awakens, John decides suddenly that she reminds him of his mother and asks her to go. She writes her telephone number on a mirror, but John erases it and rushes to a party given by Ruth. He quickly becomes bored with the boisterous affair and leaves to find Mary. Recalling that she lives in Murray Hill, he goes there by taxi, searching the neighborhood in vain. When he returns to his apartment, Mary is there cooking dinner. They get into bed, exchange names, and begin a relationship.