When Roxton happens upon a hangman's noose dangling from a lonely tree in the jungle, he's suddenly transported back to the American West where he finds himself at the end of the rope. Facing him is Challenger, but in this world he's known as Sheriff Jack Challenger, a cruel lawman who neither recognizes Roxton nor listens to his plea of innocence.

Saved by a rancher's widow, Roxton begins a strange journey to clear his name and find his way back to the Lost World. Along the way he runs into all of his friends but none of them recognize him -- Malone is a cold-hearted gunslinger, Veronica runs the local saloon and trading post, and Marguerite is the beautiful widow who saved Roxton's life. As Roxton struggles to make sense of it all, he is drawn to a final showdown in the saloon, where he must face his friends in a deadly shootout.