Highway 13

A string of truck crashes along US Highway 13 near Bishop, California begins to claim lives, culminating in Henrietta Denton's fatal accident. Hank Wilson, a Norris driver, stops to help and becomes entwined in the investigation as the accidents grow suspicious and more deadly.

Frank Denton confronts J.E. Norris about the lack of a rigorous investigation into the crashes and urges bringing in a war buddy to look into it. He hints at insider involvement and questions the company’s handling of the incidents.

Hank encounters Doris, who works at the Clover Cafe and Garage, during a routine route. They discuss Hank's hoped-for raise and his dream of buying his own truck, while a spark of romance begins to form.

Mary Hadley, the personnel supervisor, doubts Hank deserves the raise, while Hank senses a deeper issue behind the crashes. Frank thanks him and approves the raise, tying his confidence to Hank’s cooperation.

After the sixth accident, investigator George Montgomery is hired undercover to shadow Hank. They stop at a diner, and Hank shares news of the raise with Doris, while George narrows the focus to the Clover Cafe and suspects insider involvement tied to Pops.

Before returning to the warehouse, Hank stops at the Clover Cafe with a ring and proposes to Doris, who accepts. The engagement marks a personal turning point amid the mounting suspicions.

Back at the Norris warehouse, a hand releases the brake on Hank's truck, causing it to back into George Montgomery and kill him. Hank is immediately suspected of homicide, deepening the peril around him.

Keller, an attorney for the insurance company, informs Hank that George had been in contact with them and suggests a deal: Hank can be reinstated if he helps prove the crashes were intentional and uncover the motive, with discretion kept quiet.

Hank visits Mary’s office and they kiss, witnessed by others through the door. The next day Doris confronts Hank over rumors, and she ends their engagement, unsettled by the perceived affair.

Hank and Keller decide to change methods and pursue the truth more openly. Hank informs Doris about Pops and the gang, and Doris realizes Hank’s information puts them in danger.

Doris warns Pops that Hank has him pinned to the wall, and Pops warns Mary that Hank is dangerous. Hank overhears the exchange, confronts Pops, and Pops attacks him and ties him up.

Aunt Mert arrives, pleads for Pops to reconsider, but Pops loads Hank into his truck and orders Aunt Mert to stay behind. Doris slips into the back unnoticed, hidden from sight.

Pops meets with Frank and Mary and they plot driving to the crest of a hill, where Pops will jump out while Frank and Mary drive behind to pick him up. The plan is meant to frame Hank and protect the insurance scheme.

Pops reaches the crest, sets the throttle, and jumps. Doris hangs in the back, trying to wake Hank, while Frank’s car hits Pops and leaves him behind. Hank then manages to stop the truck in the road, watching as Frank and Mary attempt to follow through with their plan.

Hank declines the reward, expressing dismay at how things turned out. Doris asks about the red truck in Bakersfield, suggesting a future pursuit or relocation as the story closes on an unsettled note.