Aliens invade Earth, and decide that Muhammad Ali should box Superman (with his powers removed), and that the winner would challenge the leader of the aliens. Without his powers, Superman gets creamed by Ali. After resting on Earth for a while, Superman gets his strength back and sabotages the alien fleet. Ali beats the leader of the aliens, and the world is saved. In the last few pages of the comic, Ali reveals that he has figured out Superman's secret identity (based on very little information), but will keep it a secret because he's such a cool guy. The comic ends with him saying "Superman, we are the greatest."