On Halloween night, Bud Fontaine Jr. [Billy Gray] and a couple of friends break a window at a seemingly abandoned house, only to scatter when an older man steps outside and glares with a stern, almost judicial gaze. Bud explains the incident to his father, Robert Fontaine Sr. [George Murphy], who soon learns that the new neighbor is Dr. Paul Mahler, known to locals as Matlock [Kurt Kasznar], a man who keeps his distance and refuses the offer to repair the damage.
The next morning, Bud befriends a stray dog he names Boy [Gary Stewart], and heads to Matlock’s house to pitch a newspaper subscription. Matlock declines, and Boy darts inside, knocking over a stand; Bud saves the moment, retrieves Boy, and returns home. The family grows fond of the dog, and Bud’s parents decide to let him keep Boy, adding a gentle, hopeful note to the tense start.
A day later, Bud accompanies his father to deposit used heating oil for their modest orchard operation. As they drive, Matlock’s car nearly swerves into Boy’s path, a near-miss Bud interprets as a deliberate act. At home, Bud learns he’s invited to a birthday party, and while shopping for a gift he buys a dog license and leaves Boy at home. When he returns, he finds Boy poisoned outside Matlock’s house, a discovery that jolts the family and tightens Bud’s resolve to seek answers.
Bud’s father confronts Matlock, who denies the charge with practiced calm. Bud wants the truth publicized and tries to alert the local press, hoping William J. Wardlaw [Lewis Stone] will publish the story, but Wardlaw warns that Bud needs solid proof before any sensational claims go to print. Undeterred, Bud uncovers a crucial clue at a grocery store: Matlock had purchased rat poison using his valuable gold watch. The trail continues as Bud sneaks into Matlock’s garage and finds an opened box of rat poison and a vehicle registration connected to Mahler. Wardlaw attempts to dial the address, only to discover the number has been disconnected, and he cautions Bud to return the evidence quietly, lest the truth disappear.
Determined to press the investigation, Bud hitchhikes to Mahler’s address, only to discover a desolate, abandoned beach house. That night, he rides a motorcycle back home, and his parents are upset by his absence. His father orders him to stay in, but Bud slips out again to return the registration, only to be caught by Matlock, who screams in fury. In a moment of reckless retaliation, Bud damages the spout of the oil tank, triggering a spill that threatens the orchard’s wintering needs and unsettles the entire farming community.
Back with the farmers and their families, the oil shortage adds strain to an already fraught situation. Bud and the other growers muster a plan to reach Matlock for answers, but the line between suspicion and revelation remains murky. In a pivotal turn, Wardlaw reappears as the public face of the investigation, and Matlock is described by others as “Dr. Mahler,” a title that carries both professional authority and personal shame. The tension peaks when Wardlaw facilitates a tense exchange that brings Dorothy Mahler [Katherine Warren] back into the narrative, reuniting her with her husband. Dorothy’s presence underscores the emotional cost of the Mahler family’s estrangement; Mahler explains that his gravely ill son needed an operation but died during surgery, a loss that left him to blame himself and contributed to the collapse of his marriage.
The truth edges closer when Mr. Wetzell [Stanley Andrews], a fellow farmer, admits he accidentally killed Boy by leaving poisoned meat for coyotes. Bud’s response is unexpected: he forgives Wetzell, choosing mercy over vengeance and recognizing the complexity of mistakes in a fragile community. In a gesture that signals a new beginning, the Mahlers offer Bud a fresh sign of goodwill—a new puppy named Rex—before Bud heads off into the road, carrying the memory of a night that forced him to weigh courage, responsibility, and compassion in equal measure.
