Two brothers who share a ranch have been feuding over the money gained from stock sales. His older brother Pinto berates him for buying a high strung horse for his intended, Karen, and demands the rest of the stock money. Curly, the younger brother, refuses to give the money back. Pinto gives him until noon the next day to rethink that decision.
That evening, Pinto goes to Karen's room and attempts to pay her off so she'll leave town and leave Curly alone. Karen attempts to seduce him for more of the money and ten turns him out when it doesn't work.
The next day, as Karen and Curly are preparing to test out the new horse, Pinto confronts his younger brother and again demands the money from the stock sales. He discovers Curly has hidden it in his saddle bags and move to take them. Curly shoots his brother and he and Karen ride for Tascosa.
Matt rides out after Curly and tells Festus to stay behind. Festus disobeys him and follows Matt down the trail. Matt is ambushed and shot off his horse but Festus kills the hired gunman.
In Tascosa, Curly arranges with a friend and Kurt Relko, who controls the town, to be hidden from the law. He doesn't know that Karen is also involved with Relko until he witnesses them making a deal for his money.
Matt and Festus reach Tascoso, locate the man in charge, and force him to admit his part in Matt's shooting. He takes them to where Curly and Karen are hidden. Curly shoots his revolver through the door, killing Relko, and then attempts to shoot Karen. Matt kicks down the door and kills Curly.
Matt angrily dismisses Karen from the room and then tells Festus that Pinto had said the shooting was done by a complete stranger. Festus points out that if Matt had taken that to court, Curly would have been free. Matt agrees and then says that Curly wouldn't have needed a jury to tell him he was guilty.