After a long chase on horseback, Red Ryder captures a rustler, Joe, who tells Red that he has a child to feed and that they are living in an abandoned mine shaft. Red asks Joe to take him to the mine and there he meets Mary, Joe's six-year-old daughter. Red informs them that he will arrange for food, lodging and a job for Joe at his Painted Valley Ranch. On his way back there, Red meets his aunt, the Duchess, ranch hand Buckskin and ward Little Beaver repairing a fence and suggests that they all go on a fishing trip before the roundup starts. Elsewhere, rancher and saloon owner Faro Savage and his two henchmen, Goldie and Windy, visit Dan O'Connor's ranch to complain about newcomers fencing off the open range. Savage suggests that their cattle be rustled, forcing them to leave, but Dan states that he wants nothing to do with Savage's scheme. After Savage threatens him, Dan's daughter Sheila draws a gun and tells Savage and the others to leave. Later, when Red receives a telegram from Dan seeking his help in averting a range war, he, Buckskin and Little Beaver head out. Meanwhile, Savage's men rustle cattleman Bill Evans' stock and kill him. On his way into town to meet Red, Dan witnesses the rustling and finds a gun Savage dropped beside Evans' body. Dan returns to his ranch with the body, tells Sheila that he suspects that Savage is involved and then heads back to town. However, Dan and Red miss meeting each other in town, and while Red heads for Dan's ranch, Dan is informed that Red is waiting for him in Savage's saloon. Unaware that Savage suspects that he has found the gun and is setting a trap for him, Dan goes to the saloon. When Red and the others arrive at Dan's ranch, Sheila gives them a cool reception, as she feels that she and her father can look after themselves. Later, Windy reports to Savage that while he and Goldie were trying to get Dan to talk at Savage's ranch, Dan tried to escape and Goldie shot and killed him. Assuming that the gun is at Dan's ranch, Savage heads there. Sheila, meanwhile, tells Red about her father's suspicions regarding Savage, with whom Red has had previous dealings and knows to be a crook. When Savage shows up at the ranch, Red and Sheila tell him that they know about the gun. After Windy and Goldie send Dan's horse into the ranch, Red and Sheila take Savage with them as they search, unsuccessfully, for Dan. On his way back into town, Buckskin meets Duchess, who has come to visit, and finds Dan's body hidden in some brush. Buckskin takes Dan, who was clutching a birthday card from Sheila's twelfth birthday when killed, to his ranch. Meanwhile, Sheila goes to Savage's saloon, searches his desk and escapes. As she rides off, Goldie tells Savage he is quitting, so Savage kills him then claims that Sheila did it. The sheriff and a posse ride after Sheila, while at the saloon, Windy informs Red that Sheila has killed Goldie. Calling Windy a liar, Red fights with him and beats him. The next day, Windy follows Red and Buckskin and sees them find Sheila hiding out in a shack. When Red shows her the crumpled birthday card, she realizes that on her twelfth birthday, her father hid her present in the stump of a tree near the ranch house and that the gun is probably hidden there. Windy overhears this and leaves ahead of them. When they reach the stump, Red finds the gun and a signed note from Dan giving his testimony. However, Windy gets the drop on them and intends to kill all three, but Duchess, who has been following them, shoots the gun out of Windy's hand. Red then talks Windy into admitting that Savage killed Goldie and wants Sheila out of the way. When the posse returns to town, Savage and the sheriff find Red and the others waiting in Savage's office. Red asks the sheriff to arrest Savage for the murder of Evans, Dan and Goldie. In retaliation for his friend Goldie's murder, Windy tells the sheriff that they have found the gun that killed Evans and reveals what he knows about the other deaths. Savage tries to flee, but Red catches him and, after a fight, hands him over to the sheriff. Later, Red, Sheila, Buckskin, Duchess and Little Beaver finally set out on their fishing trip.