[1] Lois Conway (Williams) works as a music teacher at a local high school in a small town, where recently a woman was found murdered.

When she starts receiving notes from an anonymous admirer, she suspects her favorite student Sandy (Wilder) is responsible, and tells him they could never be lovers.

The notes grow more violent, and when, in her latest letter, she is invited to meet at the school's lockers at night, Lois decides to visit, hoping to stop the young man.

There, she is attacked by an initial shadowy figure, whom she later identifies as Leonard Bennett (Saxon), the high school's star football player.

Soon, the story spreads around school, and with gossip surrounding Lois allegedly pursuing Leonard, both her personal and professional lives become a mess.

Graham wants to continue prosecuting Leonard for breaking into Lois' apartment, but she wants to drop the case and orders him to bring the boy home.

[1] In a 1951 draft of the story, Harry Graham was a fellow teacher instead of a policeman, and Leonard Bennett was revealed to be responsible for the murders, before being killed.

Russell had no time to work on the screenplay, as she became busy with back-to-back Broadway productions, including Wonderful Town, The Girl Rush, and Picnic.

As a result, she did not return to the project until 1955, when Marcus and scenarist Meadow had made further revisions to the script under the working titles The Lie and The Hidden Heart.

He received the co-starring role after several screen tests, and the studio attempted to make him fill the void left by actor James Dean's death.

[1] In her autobiography, Williams noted: I thought it was a curious choice for Universal to offer me the lead in a 'dry' psychological thriller, and I wasn't sure the public would accept me without my glittering crowns and sparkly swimsuits.

Nonetheless, Universal offered me $200,000, which was more than I ever made for a single film at MGM in or out of the water .... Later, after we had started shooting, Rosalind Russell came up to me at a party and said, 'I hear you're doing my script.'

[..] While Esther Williams is the top-billed star of The Unguarded Moment, it is Andrews' unexpectedly creepy performance that hijacks the film and imbues it with an underlying mood of malice and menace.