On a quiet country road, a driver offers a lift to a woman, and the moment darkens as he attacks her. The crime shocks the community, and her body is later discovered by children playing in a hay shed, a grim reminder of danger lurking in familiar places.
Meanwhile, Jean Painter [Christina Gregg] is a teenage schoolgirl waiting for a bus on that same tranquil lane. She has just been babysitting at The Chequers, the village pub owned by her uncle Ron [Conrad Phillips], and the routine of everyday life feels suddenly charged by a strange phone call. The nearby phone box rings, and, curious, she answers. What begins as a mysterious conversation with an unknown man becomes something she eagerly anticipates, and she agrees to chat again the next day. At home, she confides in her younger sister Ann [Janina Faye], imagining what the caller might look like and fantasizing about his voice.
The next day, Jean answers the phone again at the same time and place. She falls in love with the man, though she tells him a false name—Samantha—to keep her caller close. On the third day, the routine is broken by the absence of the call. She skips the bus in hopes of hearing from him, but a passerby uses the phone box and interrupts the moment. On the fourth day, the man calls, irritated that she missed him, and he flirts with her, professing his love for her voice. They arrange to meet in person the following day.
Worried by newspaper reports of the murdered girl, Jean's father [Cyril Raymond] bans her from going to The Chequers that night and also bars Ann from attending a school dance. The next evening, Jean pretends to go into town with Ann to the cinema, but instead she takes the bus toward the rendezvous. She notices a drunken man wandering along the lane, and fear lingers as she runs into a field and hides in a shed, daydreaming about the man’s voice.
Meanwhile, the man enters The Chequers and orders a drink. He is the same caller from the phone box. Realizing how reckless she has been, Jean hurries to The Chequers, where she finally hears the man’s voice and spots his face as he uses the phone box. Ann, worried about her sister, has left the cinema early and arrives at the phone box to search for Jean. When the phone rings, Ann answers briefly and then calls the police.
Jean recounts the events to Ron and tries to reach the phone box once more, urging Ann to hide. But it’s too late—the man arrives, thinking Ann is Samantha, and drags her toward his car as the vehicle speeds away. Moments later, Ron arrives in his own car, gives chase, and forces the kidnapper’s car off the road. A struggle ensues between Ron and the assailant as the police close in, bringing the tense sequence to a dramatic, consequential close.
