While teenager Mickey Clark, a lover of hot-rod automobiles, and his friend, Todd Powell, work on Mickey's car, Mickey's father witnesses an accident in which a man driving too fast kills his own daughter. At home, Mr. Clark warns Mickey not to drag race, but later, while taking the family for a drive in his new car, Clark drives recklessly and hits the automobile of Judge Roger Tanner, who is driving with his daughter Susie. Clark denies culpability in the accident, but later, in Judge Tanner's own court, Clark is contrite, and Tanner lets him go. At the local country club, Mickey's older brother Jeff, a Navy flier and war hero, apologizes to Susie for his father's insolence, and they start dating. Rusty and Peggy, the girl friends of Mickey and his friend Todd, meanwhile, admire Jeff's bravery in battle and harangue Mickey and Todd into entering a drag race. A policeman breaks up the race, and the drivers and their parents are called into court, where the judge upbraids them for their dangerous recklessness, explaining that 37,000 Americans were killed in car accidents the previous year. The judge releases the boys into the custody of their parents. Later, while driving the family car to pick up his mother at the railroad station, Mickey is chased by the police for careless driving and races his mother's train, barely missing it. That night, while Rusty, Mickey, Peggy and Todd have a party on the beach, they hear a news flash on the radio that an unidentified hot-rod driver has died after his car plunged into the ocean. The group goes to the morgue to find out who the driver was, and Rusty is locked in when the guard arrives. The others flee, and during a police chase, Mickey crashes into two cars, killing Todd and seriously injuring an unidentified woman. He flees the scene of the accident and returns home, quietly entering his room. Downstairs, Jeff and Susie announce their engagement to Mr. Clark. Their celebration is interrupted by a news flash of a fatal car accident involving Mrs. Clark. Jeff and Mr. Clark rush to the hospital, while Susie tells Mickey about the accident. He goes to the hospital, and after hearing that his mother has a chance of surviving, he confesses that it was he who caused the accident. The police pick up Mickey on suspicion of manslaughter. Rusty, who panicked when she saw Todd's body brought into the morgue and weighed, is arrested, and tearfully tells a judge that she encouraged the boys to drive fast. When Mickey is brought before a judge, Mr. Clark admits that he is equally culpable in his son's crime because he seldom practiced what he preached about driving safety. When Mrs. Clark is fully recovered, Mickey confesses to her that he caused the accident. Later, Mrs. Clark safely drives her husband to pick up Mickey, who has finished his jail sentence.