When he is wounded during a stage robbery, masked bandit Monte Jarrad drops a rifle engraved with his name.  Having only the robber's name and a vague description, the Sheriff of Payneville offers a $1,000 reward for the arrest of "tall and skinny Monte Jarrad who travels with a half-wit named Uncle Roscoe." Consequently, when long- limbed cowpoke Melody Jones rides into town with the initials "MJ" carved into his saddle, the townsfolk of Payneville mistake him for Monte and think that his sidekick, George Fury, is Uncle Roscoe.

Delighting in the deference paid to him by the townsfolk, the gun-shy, mild-mannered Melody begins to swagger like a gunslinger until Cherry De Longpre, the beautiful daughter of a local rancher, warns Melody that a gun is trained on his back and shields him as they ride out of town.  Cherry escorts George and Melody to her ranch, and after explaining the case of mistaken identity to Melody, admonishes him to leave the territory as soon as possible.  Melody takes her advice, and after he leaves, she visits the barn where she is harboring the wounded Monte.  After warning Cherry to forget Melody, the jealous Monte sends her brother Avery to town to find Leo Gledhill, his accomplice in the robbery.  Melody is charmed by Cherry until he realizes that she has deliberately set him up as a decoy and returns to the ranch to confront her.

That night, Cherry is shocked to find Melody in her bed, and after telling him that Monte is her childhood friend "gone bad," she asks him to hide in her room until morning.  While Melody complies with Cherry's request, George rides into town and learns that the Sheriff, the express company, the cavalry and the Cottons, a family bent on avenging Monte's murder of three of their kin, are all in pursuit of the bandit.

The next morning, Melody meets George at his camp, where George hands him a note addressed to Monte from stagecoach driver Ira Waggoner, demanding his share from the robbery.  Cherry follows Melody to camp, and after bursting into tears for betraying him, she asks him to take Monte's saddle and lead the posse away from town.  Melody, enchanted by Cherry, straps Monte's saddle on his horse and hands her his handkerchief to her as a remembrance.  Cherry then returns to the ranch where Monte, who is now recovered, tells her that he will send for her and then departs.  Posing as a tough gunslinger, Melody rides into town and meets Waggoner, who pulls a gun and demands his money.  Wagonner is interrupted by Leo, who orders Melody to accompany him out of town at gunpoint.

On the outskirts of town, Leo challenges Melody to a duel, and the bungling Melody is saved by Cherry, who trains her rifle on Leo and orders him to follow George into the desert.  While George leads Leo away, Cherry offers to show Melody where the money is hidden if he agrees to wait until spring to return it, thus allowing Monte time to leave the territory.  After Melody agrees to Cherry's terms, she takes him to a shack where they are greeted by Luke Packard, an agent of the express company.  After informing them that he has sent for the posse, Packard offers to allow Melody to escape in return for the money.  Knowing that the posse will hang Melody if they catch him, Cherry tells Packard that the money is hidden in a trunk by the window.  As Packard bends to open the trunk, a shot rings out and he falls dead.  When George stomps in immediately afterward, Melody thinks that he shot Packard but soon realizes that Monte is the killer.

After they stash Packard's body in the trunk, the Sheriff arrives and offers Melody his freedom in exchange for the stolen funds.  When Melody refuses his offer, the Sheriff sits on the trunk, causing the top to dislodge, thus exposing Packard's body.  In the confusion, Cherry gallops off and Melody follows, but loses her.  In search of Cherry, Melody rides to the De Longpre ranch and is there confronted by Monte, who orders him to swap clothes.  Insanely jealous, Monte plans to obliterate Melody's face so that he will be mistaken for the fugitive.  As Melody taunts Monte by telling him that Cherry is no longer his, Cherry enters the room and orders Melody to the barn where George lies, wounded by the vicious Monte.

When Monte's gang arrives with news that the posse is approaching, Cherry grabs her rifle and runs to the barn to protect Melody.  Avery and her father join her there.  After admitting that he returned to Payneville to help Cherry, Melody takes Pop's gun and challenges Monte to a shootout.  Monte shoots Melody in the arm and leg and is about to finish him off when Cherry shoots the gunslinger in the back.  Thinking that George shot Monte, Melody collapses.

Later, after they both recover from their wounds, Melody offers George the reward for Monte's capture.  When George declines it, Melody realizes that Cherry must have shot Monte.  Believing that she intended to shoot him instead, Melody accuses her of being a bad shot and begins to saddle his horse to leave.  To prove him wrong, Cherry shoots a hole in his hat.  Finally comprehending that she shot Monte to save his life, Melody strides back into the house and embraces Cherry.