A stranger comes to a very small town that is suffering from guilt and gets little cooperation and much hostility while figuring out what happened there.
One-armed John J. Macready (Spencer Tracy) gets off a train, and Mr. Hastings (Russell Collins) says the train has not stopped there in four years. Macready asks for a room in the hotel and is told none are available, but he insists. Hector David (Lee Marvin) tells the hotel clerk Pete Wirth (John Ericson) he wants to know everything about him and says he will crowd him. After his shower Macready finds Hector laying on his bed and is given a hard time. Macready tells the clerk he is staying 24 hours. Doc Velie (Walter Brennan) tells him where he can find a car. Reno Smith (Robert Ryan) arrives and tells Coley Trimble (Ernest Borgnine) to sit down. Reno asks to get information on Macready from a private detective in Los Angeles.
Macready walks to the jail and finds the sheriff Tim Horn (Dean Jagger) laying down in a cell and is offered a drink. Macready asks for information so that he can go to Adobe Flats because he is looking for Komoko. Smith apologizes to Macready and invites him to go hunting. Smith says Komoko was a Japanese farmer who was sent to a relocation camp. Liz Wirth (Anne Francis) arrives in a jeep, and Macready rents it for $10. Macready drives off, and Smith blames her.
The sheriff tells Smith he does not want any trouble. Smith gets a telegram there is no information on Macready. Coley is worried that he will find out about Komoko. Smith says Macready brought an infection. Pete objects to killing, but the others follow Smith. Tim tells Doc he wants to resign because he is not respected. Tim says he did not investigate. Doc tells Tim not to quit.
Macready finds a burned house and picks a wildflower. He sees a windmill and finds water in the well. Coley watches him with binoculars. He follows the jeep in his car, toots his horn, and drives into the jeep several times. Macready goes off the road and stops, but Coley stays on the road.
Macready returns to town in the jeep, and Coley accuses him of crowding him off the road. Macready offers to pay for his damages, and Coley says he could be hurt. Macready says he is leaving now. He asks Pete about transportation, but there is none until the next day. Liz tells him that the jeep is no longer for rent. He asks her what is wrong with the town. He asks why she has not left, but she says she stays there because of her brother. She leaves in the jeep.
Smith puts gas in his car and asks Macready about his arm. He says it happened in Italy. Macready says he was forced into retirement. Smith shows his contempt for “Japs” because of Pearl Harbor. Smith says kids burned down Komoko’s place. Macready believes businessmen might be interested in Adobe Flats because of the grave with wildflowers that is not marked.
Doc lets Macready use his phone to call the state police, but the operator Pete tells him to mind his own business. Doc says they will kill him, but he is apathetic. Doc says he can get out of town in his old hearse. Macready tries to start it, and Hector says it is the wiring. Doc tells him to keep his nose out of his business, and Hector rips out some of the wires.
Macready walks to the train station and writes a telegram to the state police, and Mr. Hastings accepts money to send it. Macready goes in a place and orders coffee. Coley bullies him off “his stool.” Coley pours ketchup in his coffee. Coley asks if he is a “Jap-lover.” Macready pays for the coffee, and Coley stops him and asks for a fight. Macready uses karate and judo to beat Coley and takes his knife. He accuses Smith of killing Komoko with others and tosses him the knife.
Macready gets his suitcase and sits down. He gets his telegram back and accuses Hastings of telling Smith about his telegram. The sheriff says that is illegal, but Smith takes his badge and pins it on Hector, who warns Macready and walks out with Smith. Macready takes a bottle out of his suitcase and shares it with Doc and Tim. Doc says something terrible happened, but now they have a second chance. Doc urges Tim to act, but Tim says he is sorry and leaves. Macready says he came there to perform his last duty in life. Macready criticizes Pete and offers him the bottle. Macready asks what happened. He says Komoko had a son who was buried in Italy. He says the son died saving his life, and he brought his medal. Doc says Komoko dug a well. Pete says Smith tried to enlist after Pearl Harbor but was rejected. He says Smith started the fire and shot Komoko. Pete calls his sister and says he is getting Macready out of town.
Hector has a gun and sits outside the hotel at night. Pete invites Hector inside, and Doc knocks him out with a fire hose. Macready walks out and gets in the jeep that Liz drives off. She stops for water. Lights go on, and Smith shoots at Macready. Liz tells Smith she did as he said. Smith says there are too many witnesses, and he shoots her. Smith shoots at Macready and then walks toward the jeep. Macready uses the jeep to put gas in a bottle and plugs it with his tie. He lights the tie on fire and throws the bottle at Smith, whose clothes catch on fire. Macready helps put out the fire.
Macready drives back in Smith’s car, and Tim says he will take care of Smith. Macready tells Pete his sister was killed. As the train arrives, Doc hopes the town will come back. Macready hands him the medal and gets on the train.
This drama depicts the guilt and intimidation when a racist bully forces others to submit and help him protect his crime. One courageous man is able to uncover the crime in a difficult situation that offers little other escape. He only wanted to present a medal to the father of the man who saved his life, but the guilt and fear of those involved in the crime betrayed them into committing further crimes. The drama reflects the racism that was fueled by the violent Pacific War.