High Noon tells the story of a lawman named Will Kane (Skerritt) who has just married a young bride, Amy (Thompson), promising to leave his dangerous career and settle down for a quiet life. Just as they are about to leave, word comes that a vicious killer Kane had sent to prison years earlier, is coming to town on the noon train seeking vengeance. Kane attempts to rally the town to fight the gunman, but not even his former deputy Harvey (Diamond) is willing to help. Harvey's cowardice infuriates his girlfriend, Helen (Alonso), whose romantic past with both Kane and with the arriving gunman convinces her to pack up and leave town. As the dreaded noon hour approaches, Kane realizes he must stand alone against the coming storm.

Un hombre de la ley llamado Will Kane acaba de casarse con una joven novia, Amy, con la promesa de dejar su carrera peligrosa y establecerse para una vida tranquila. Cuando están a punto de partir, recibe un telegrama en el que dice que vuelve un asesino que había enviado a la cárcel años antes, y viene a la ciudad en el tren del mediodía buscando venganza.