Gus' teacher Lydia Marble (Joanne Dru) manages to curb the boy's prankishness, and along the way falls in love with Jennings.

[7][8][9] Dave Jennings is so focused on his Los Angeles-based business that he neglects his precocious five-year-old son Gus, who is constantly creating havoc in order to get his father's attention.

As the next three weeks pass, Gus becomes contented and well-behaved, but on Dave's scheduled parent participation day, the businessman instead sends a truckload of toys to the school.

That night, Dave comforts a frightened Gus by allowing him to sleep in his bed, and, realizing that he no longer needs Lydia for instruction on child care, confronts her with his new knowledge.

Fearing the worst, Dave keeps the appointment and discovers that the money-grubbing, immoral Joyce is broke and claims that their Mexican divorce is not legal.

Determined to win, no matter what is revealed about Joyce in court, Dave does not listen to the pleas of his friends that he think of Gus and end the confrontation quietly.