1873: After busting up a group of train robbers hired by Kang the Conqueror, the three time displaced Avengers and the heroes of the old west learn how to break into Kang's citadel. Hawkeye, Two-Gun Kid, Moondragon, and Thor (in his mortal guise of Donald Blake) disguise themselves and attempt to enter Kang's base.
However, Kang is waiting for them and when they enter the citadel he appears before them on a giant screen and explains that he had lured them there hoping to get revenge on the entire group of Avengers for foiling his attempt to win the Celestial Madonna. Willing to settle for the few Avengers that have shown up, he attacks them with his high tech machinery.
While back in the present, Captain America, Vision, Scarlet Witch, Beast, Iron Man, and Patsy Walker are still trapped in the cage that they have been imprisoned in by Roxxon Oil owner Hugh Jone's super agents the Squadron Supreme. Realizing that the Vision cannot phase through, let alone stick his hand through the cage, the Avengers try having the synthazoid phase his head through Captain America's shield while it's pressed up against the cage. This work's and allows the Vision to use his solar energy beams to destroy the cages controls and free the Avengers.
While back in the 19th Century, Kang unleashed a genetically mutated coyote (which has been changed into a gigantic creature thanks to Kang's 41st Century technology) he sicks it against Hawkeye, Two-Gun Kid, and Moondragon. While the heroes are occupied, Donald Blake manages to sneak into Kang's control room. When Kang realizes that the "bearded stranger" that was with the others is missing, Blake reveals himself and transforms into Thor. As the God of Thunder battles Kang, the other heroes continue to struggle against the monster the time master has unleashed upon them. It's ultimately downed by Moondragon's superior mental powers. However to be rescued at the hands of a weird woman is a major blow to Two-Gun Kid's ego.
Thor meanwhile continues to battle Kang until Kang unleashes a dissolution beam. However, as Thor continues to resist it Kang continues to increase the power and seemingly overloads the weapon and is apparently obliterated. With Kang's supposed death, the citadel suddenly vanishes. Suddenly Immortus appears before them and explains that he, Kang and Rama-Tut are all the same being, and with the destruction of Kang, the future Rama-Tut and Immortus no longer exist, with the cycle of between Kang and Immortus seemingly broken, Immortus fades from existence, much to the sadness of Moondragon.