After an experimental satellite from Kennedy Space Center falls back to Earth it breaks, releasing deadly radioactive energy. The Super Friends then receive a distress call from the West Coast saying Death Valley is being overrun by giant desert beasts. Wonder Woman and the Wonder Twins stay behind to check the Justice League computer for more information, while the rest of the Super Friends head to Death Valley. At Death Valley they find wreckage and a man who says giant lizards had nearly destroyed the town. As Superman continues to search for the mysterious giant beasts, he stumbles upon some mutated giant earthworms that he must save some teens from. As Aquaman, Batman, and Robin fight the creatures that attacked them, Wonder Woman finds out what happened via the Justice League computer and heads to NASA for more information. As Wonder Woman approaches the location of the downed satellite, the radiation turns her into a giant beast. As the Wonder Twins try to stop Wonder Woman's destruction of a military base, the radiation genetically alters them into giant beasts. Meanwhile, giant earthworms are digging holes into California's coast, which will potentially sink. To save everyone, the Super Friends must stop the creatures and turn them and the "Wonder" heroes back to normal.

Three Kryptonian villains from the Phantom Zone escape and expose Superman to red kryptonite causing him to age rapidly. The rest of the Super Friends get trapped by the villains and only Superman can free them from the Phantom Zone. Meanwhile, the Justice League Computer tells Superman the only possible antidote for his rapid aging is blue kryptonite. Since blue kryptonite is harmful to Bizarro, it may have an opposite effect on Superman. Superman must take the Supermobile to go to the site where Krypton blew up and get the blue kryptonite in time to save the other Super Friends. Using the ray device the three villains stole from Superman, he sends the Kryptonian villains back to the Phantom Zone.