Bruce Patterson, a mild-mannered professor of archeology who is relentlessly pursued by his amorous female students, leases the apartment of his fiancée, Helen Bushmill, while she is on a trip to Paris. The age-conscious Helen has never told Bruce that she was previously married, or that she has a 17-year-old daughter, Libby. Consequently, when Libby appears at her mother's house, Bruce mistakes her for one of his passionate students and sends her away. Libby pretends to be an unhappy delinquent, however, and the professor allows her to stay. Though Libby's attentions are soon drawn to Bruce's neighbor, law student Mike Polaski, the helpless professor continues to be menaced by love-sick teenagers. Mike finally convinces him that the only way to stop the girls is to do the chasing himself. Bruce takes the advice, gets roaring drunk, and, minus his trousers, chases all the girls on a nearby beach. His escapade is witnessed by the horrified Helen, who has just returned from Paris. At first she breaks off their engagement, but Libby and Mike easily persuade her to change her mind.