Lucy (Irene Dunne) and Jerry (Cary Grant) are a glamorous, happily married couple. Their life together is carefree and full of fun. Until a slight misunderstanding avalanches into a divorce and even their dog becomes fuel for their fire. They couldn't live together, but after the divorce, they quickly find they can't live without each other. Lucy meets Dan (Ralph Bellamy) and decides he's the man to help her forget Jerry, only Jerry keeps popping back into her life, and more importantly, into her apartment, destroying bit by bit Lucy's simple dream of marrying a nice, simple man. So when Jerry finds love and decides to marry, Lucy returns the favor, showing up at the future in-laws as Jerry's zany sister. Mad and still hopelessly in love with each other, Jerry and Lucy end up in the country where Lucy engineers their reunion.