DR. WILMA TUTTLE, beautiful but prim and conservative, flees the beach at night, clearly upset, eventually hitching a ride with a TRUCKER. Once home, Wilma climbs into bed, awaking to her HOUSEKEEPER in the morning. As the night's horror returns to her, Wilma remembers how it all began the previous morning......Wilma teaches psychology at a small Southern California university. Among her STUDENTS is a handsome but disturbed young man, BILL PERRY, who frequently flirts with her in class and tries to make dates. Wilma reports the boy to the DEAN, canceling her appointment with Bill after school by leaving a note on her office door. When Bill sees her leaving campus, Wilma informs him he should see the Dean. Wilma misses her bus during their conversation, and Bill offers her a ride.Wilma and Bill chat as he drives her home, and she does a psychological analysis of his character, probing into his dysfunctional home life. Eventually, they end up on a cliff overlooking the beach. Although Wilma subliminally responds to Bill's easy sexuality, she begins to resist his advances. When he strong arms her, clearly intending to rape her, Wilma struggles, finally hitting him over the head with a heavy instrument that Bill uses for catching mollusks. Frantic, Wilma makes it appear as though Bill drowned, tossing his body off the cliff......Back in the present, Wilma tries to get through the day, even though she's racked by guilt and anxiety. When Bill's guardian shows up, WARREN FORD, a lawyer, Wilma tenses, but Warren proves a handsome, charming man indeed. He also claims that Bill is a "bad boy," and he's suddenly turned up missing. Warren also carries a letter Bill received from SUSAN, a foreign exchange student in Wilma's class, who loved Bill but could not get him to love her back. She claims in the letter that she's pregnant.Tension builds in Wilma until she collapses and is hospitalized. When she comes to, she learns that Bill's body has been found. A dogged detective, LT. TED DORGAN, investigates, soon concluding that it was murder. Susan, the foreign student, is the prime suspect, but she admits that she wasn't really pregnant. Wilma does her best to appear innocent, but the strain increases. Lt. Dorgan puts on the pressure when he asks Wilma for Bill's exam paper - one in which he was assigned to describe a particular psychological profile. They suspect that whoever killed him fits the profile. Wilma finds the exam, and it's clear that Bill was writing about her. Further, Wilma finds that the note she left for Bill, telling him she couldn't see him that day, is missing. She writes a copy, hoping it will help exonerate her.Lt. Dorgan brings in the truck driver with whom Wilma hitched a ride, hoping that he'll be able to identify her. In the meantime, Wilma has fixed herself up, becoming a bit sexier, having gone out with Warren Ford, the guardian, the night before. Because Wilma's blossomed so since the night of the murder, the Trucker doesn't recognize her.Wilma and Warren go to the police lab, where Dorgan and a feisty lab technician, DR. ROMLEY, go over the evidence, from which they have easily (and correctly) concluded that the killer faked Bill's drowning. When their conversation becomes particularly vivid, Wilma loses it, leaving the room after insulting Dorgan and Romney. Warren takes Wilma to a prizefight, but the young fighter reminds her of Bill, triggering another hysterical outburst.Back home, Warren kisses Wilma, and then, after leaving and seeing that Dorgan is interviewing her housekeeper, Warren goes back and proposes marriage to Wilma. The startled professor initially demurs, but then accepts. They announce their engagement to Dorgan at police headquarters. By now, however, Dorgan suspects Wilma of the murder, and he asks her questions. Wilma trips herself up when it comes out that the note she left for Bill was taken by Dorgan himself. Therefore, he knows that she wrote a copy to throw off police. Wilma confesses to the crime and Warren defends her. He does not deny that she killed Bill and tried to conceal the crime, but he hopes to convince the JURY that she acted in self-defense and that her only true crime was fear. Watching the proceedings, Dorgan, who has come to like Wilma, is certain that she'll win - if nothing else, because of the romance that has developed between her and Warren.