Lone wolf, who is stirring up the Indians against the wishes of his elders, gets the job of scout at the fort. When he hears of the approval of the new reservation, he sends his men to trap Scott and his troop before they can deliver the information.

After years of prospecting, Jonathan finally strikes gold. He returns to town only to discover that his partner has since died and left Tommy fatherless. He decides to leave Shep with Tommy to cheer him up. Meanwhile, Jonathan's new partner isn't interested in sharing the gold, and lures Jonathan to his death.

A mysterious plague, the Purple Death, ravages the earth. Dr. Zarkov, investigating in his spaceship, finds a ship from planet Mongo seeding the atmosphere with dust. Sure enough, Ming the Merciless is up to his old tricks. So it's back to Mongo for Flash, Dale, and Zarkov.

Lin McAdam rides into town on the trail of Dutch Henry Brown, only to find himself in a shooting competition against him. McAdam wins the prize, a one-in-a-thousand Winchester rifle, but Dutch steals it and leaves town. McAdam follows, intent on settling his old quarrel, while the rifle keeps changing hands and touching a number of lives.