Superman is sought by President Luthor and the US Government in relation to a meteor the size of Australia which is on a collision course with the Earth. The reason? The meteor is a piece of Krypton, Superman's birth world. Luthor dispatches a team of heroes to bring in Superman, and Batman if he aids Superman. Fortunately, they receive some aid from surprising sources. They escape to Japan, where they're trying to meet up with a young boy who figures into their plan to deal with the kryptonite meteor. But having dispatched Luthor's heroes, the JSA takes an active hand, sending Captain Marvel and Hawkman to stop Superman and Batman. Hero fights hero, as the meteor flies ever closer to the planet!