Peter Wilson (Jack Lemmon) is a sarcastic near-sighted cartoonist, author and swinging bachelor living in Manhattan. He detests dogs and children. He is flustered by women's priorities and avoids commitment, much preferring transient physical relationships. At the office of his eye surgeon, Peter meets a leggy, eye-catching brunette named Terri Kozlenko (Barbara Harris). He likes her very much, but discovers later that she is a single mother to three children.