Truck driver Frank Webster, an escaped convict, encounters race car driver Connie Adair in a Southern Californian roadside diner, where she has stopped on her way south to enter a road race from California to Mexico. When a trucker becomes suspicious of Frank and draws a gun on him, Frank slugs him and the man falls, hitting his head on the counter. Frank then takes Connie hostage and speeds off in her open, two-seater Jaguar sports car, which Frank intends to use to cross the border into Mexico. The waitress, believing the trucker to be dead, phones the police. When Frank and Connie are forced to stop for gas, she tries to escape, but he stops her. After the police discover that the trucker is alive, but still unconscious, a waitress tells them that she thinks that Frank was his assailant, but incorrectly identifies the car in which they left. Realizing that the police will be looking for them, Frank turns onto the back roads. When a motorcycle policeman stops them, Frank warns Connie to say nothing, but the police officer only wanted to warn them that one of the car’s taillights is out. After the officer leaves, Connie pulls the key from the car’s ignition and throws it away. Unable to find the key in the dark, Frank jump-starts the car, whereupon Connie informs him that she has an extra key. After they stop to sleep, Frank ties Connie to the steering wheel, but when she slaps him, he kisses her in return. The next morning, they hear a report over the car radio that the police are searching for them, but lack a photograph of Frank. At a roadblock, they see several other racing cars headed for the track and Frank promises Connie that he will spare her life if she agrees to cooperate. Just after the police allow them to pass with the other drivers, the trucker recovers consciousness and tells the police that Frank and Connie are driving a white Jaguar. When Connie attempts to register for the race, an official informs her that the course is too dangerous for women drivers, so Frank, posing as “Bill Myers,” registers to drive the car in her place. Although Faber, one of Connie’s driver friends, is suspicious of the unknown driver, Frank manages to pass the qualifying run. That night, Connie and Frank stay at an abandoned house where Connie advises Frank to surrender. Frank then explains that he had been unjustly convicted after a driver in the employ of a major competitor was killed while trying to run him off the road. Another rival trucker swore that Frank had forced the driver off the road. Connie is sympathetic, but when the house's caretaker tells them that the police drive by every night, Frank suspects her of trying to lead him into a trap and insists upon leaving. The next day, while Frank and Connie are watching an antique car race, Faber, who is romantically attracted to Connie, questions Frank about his racing background. That night, Frank and Connie move to an abandoned cabin, where Connie again urges Frank to turn himself in to the police. After he kisses her, they awaken the next morning, entwined in each other’s arms. However, Frank still intends to go to Mexico and when Connie refuses to accompany him, he locks her in the cabin, then picks up the car from their mechanic and starts the ninety-eight-mile road race into Mexico. Meanwhile, to draw attention to her plight, Connie starts a fire. After she is rescued, Connie notifies the police that Frank is innocent and is headed for the border. Connie then borrows a car from a driver friend and pursues Frank. Faber, meanwhile, thinking that Frank is trying to win the race, speeds off after him. Frank smashes through a police roadblock, followed closely by Faber. As they jockey for position, Faber swerves off the road into a gully. Instead of continuing his escape, Frank stops to help Faber and pulls him from the wreck to safety. After Connie arrives and the police approach, Frank tells her that he has decided to turn himself in. They then embrace.