A businessman's neglected wife divorces her husband by mistake and marries his best friend by accident.

Ad-agency president Dan Edwards who, when he goes to Mexico to celebrate his nineteenth wedding anniversary, winds up getting divorced by mistake - whereupon his wife Valerie marries his best friend Ernie Brewer by mistake. Frank's future pop star daughter Nancy Sinatra has a featured role.—alfiehitchie

It's the nineteenth wedding anniversary of advertising company president Dan Edwards and his wife, Valerie Edwards. They love each other, but are far from being on the same page concerning their marriage. Dan believes that being married means he doesn't have to try, in turn neglecting Val, he who spends his evenings home happily in front of the color television. Val believes Dan has become old and stodgy, paying more attention to the company than to her, she who wants more excitement in their life. When they were dating, Val was also being pursued by Ernie Brewer, one of Dan's executives and his best friend. Ernie, a bachelor, is still a womanizer as he was when they were younger. Even on this day, Dan wants to spend the evening at home in front of the television with Ernie watching a boxing match rather than take Val out. Val sarcastically states that she made a mistake in marrying Dan over more exciting Ernie, and threatens divorce when talking to mutual friends and acquaintances, such as the family lawyer, Shad Nathan. Ernie states that he would long have given up his womanizing ways if Val chose him, he saying so only because she didn't choose him. And Dan trusts Ernie with his life and his wife. Despite Dan being oblivious to how Val is feeling, Ernie is eventually able to convince him to take her on a second honeymoon vacation to a small resort town in Mexico. A series of events in Mexico, mostly involving the town's leading businessman Miguel Santos, lead to Dan, Val and Ernie all testing out the state of their unofficial love triangle. Those tests also affect and are affected by the other three members of the Edwards household: Jeannie MacPherson, Val's very Scottish, bagpipe-playing mother, who never forgave Dan for marrying her daughter in a civil rather than church ceremony; their eighteen year year old daughter Tracy Edwards, who wants to move into adulthood by moving out of the house and in with a seemingly more experienced friend, twenty-three year old go-go dancer Lisa Sterling, it all against Dan's wishes; and their young teen son David Edwards, who has learned from friends how to manipulate both parents in a break-up situation for one's own material benefit.—Huggo