Plainview is a peaceful town, all the better for bad man Alvin Dennis and his mean brother Bob to rob the bank there. They figure small-town sheriff Pete MacKay won't pose much of a problem to them.
MacKay is having his usual chess game with Doc Lacy at the general store Jack Wright runs with wife Martha and brother-in-law Wally. A gunshot from the bank startles all. Bob has shot a teller, then guns down the old marshal when he arrives. Jack is just a meek storekeeper, but he manages to grab a gun and wing the fleeing Alvin Dennis, who is then killed by another townsman, George Henderson. And the bank's loot is saved.
Everybody, particularly banker Livingston, appreciates the bravery of the town heroes. But when the Amarillo newspaper publishes their photographs, Bob Dennis decides to return to Plainview to avenge his brother's death. A tipsy Henderson is ambushed as soon as he gets back to his ranch.
Jack could be next. A marshal comes to town to keep an eye on things, but can't stay forever and leaves after two uneventful weeks. Jack, his wife and son Billy begin to notice that their neighbors are shunning them, no longer shopping at the store or even allowing their kids to come near them.
A $2,500 reward for Alvin Dennis' capture is a pleasant surprise for Jack, but when Wally is mistaken for him and murdered in cold blood by Bob Dennis, no one is willing to help. In fact, he is offered more money by Livingston and other frightened citizens if he will sell them the store and leave town. Doc and the Wrights are ashamed of everyone's lack of support in Jack's hour of need.
He arms himself to face Bob Dennis, obviously overmatched, but Doc manages to shoot Bob. The townspeople immediately offer their congratulations and apologies to the Wrights, who are willing to forgive and forget, but Doc is not.