After a period of vacation in Hawaii, Joanna "Joey" Drayton returns to her parents' home in San Francisco bringing her fianc?(C), the high-qualified Dr. John Prentice, to introduce him to her mother Christina Drayton that owns an art gallery and her father Matt Drayton that is the publisher editor of the newspaper The Guardian. Joey was raised with a liberal education and intends to get married with Dr. John Prentice that is a black widower and needs to fly on that night to Geneva to work with the World Health Organization. Joey invites John's parents Mr. Prentice and Mrs. Prentice to have dinner with her family and the couple flies from Los Angeles to San Francisco without knowing that Joey is white. Christina invites also the liberal Monsignor Ryan, who is friend of her family. Along the day and night, the families discuss the problems of their son and daughter.