A mysterious man storms into the city room of the Daily Planet, desperate to find Clark Kent. Lois Lane informs him that Kent is on assignment, at Metropolis Bay. Superman arrives at Metropolis Bay, to clean up an oil spill. The mysterious man also arrives at Metropolis Bay. Before he can make contact with Superman, his body suddenly explodes, as he is transformed into a living comet. Superman catches the comet in his indestructible cape, and prepares to hurl it into orbit. He is stopped short by the sound of a human voice. Caught within his cape is the mutant hero, Captain Comet, and he needs Superman's help. The strange transformations plaguing Captain Comet are the result of the slow dissolution of his super-human abilities. Captain Comet believes exposure to the comet that originally gave him his abilities will resolve the matter, but, as yet, he has been unable to find it. Superman takes Captain Comet to his Fortress of Solitude. Pouring over the astronomical texts in his science library, Superman learns that the comet will reappear in 12 hours, in orbit over Chicago. Captain Comet isn't the only man looking to access the comet. Already waiting for it's arrival, in the skies above Chicago, is the man known only as Starstriker. Upon Superman and Captain Comet's approach, Starstriker fires missiles, first at Superman, then at the city of Chicago. While Superman rushes to stop the missiles from hitting Chicago, Starstriker closes on Captain Comet and uses his psychic abilities to trigger another comet attack. Once more Captain Comet's body expands as he, again, becomes a living comet. Starstriker positions himself in high Earth orbit to absorb the radiation coming off the comet., thus fully activating his mostly latent psychic abilities. Superman hurls Captain Comet into the comet. His abilities restored, Captain Comet joins Superman in taking on Starstriker, but the villain uses his newfound abilities to teleport away.
The next day, Captain Comet telepathically contacts Clark Kent, informing him that he's found Starstriker. Kent enters a storeroom to change into his Superman costume. Strangely, his suit won't compress down into the special cape pocket. Worse, when Superman tries to fly, he instead falls to the floor. Alerted by the sound of Kent's body hitting the floor, Lane knocks at the storeroom door, looking to come to his aid. Kent forces the door shut until he can get back into his clothes and resume his Clark Kent identity. Minutes later, Kent, as Superman, travels to the Justice League Satellite. Wonder Woman, on monitor duty, offers to aid the Man of Steel, but Superman declines. Following Captain Comet's telepathic signal, Superman uses the transporter to arrive at the Barringer Meteor Crater, in Arizona. Starstriker creates energy duplicates of himself to take down Superman. Once unconscious, the Man of Steel is imprisoned next to Captain Comet. Moments later, the Man of Steel breaks free. While Starstriker has caused Superman to forget how to access his abilities, those abilities, including his invulnerability, have not been lost. Superman frees Captain Comet, who uses his psychic abilities to unlock Superman's mind. Superman squares off against Starstriker. Captain Comet discovers that Starstriker has drawn seven comets from space, and set them on a collision course with Earth. Superman flies into space to deal with the comets, while Captain Comet battles against Starstriker. Superman shatters one of the comets in such a way that the debris impacts with the other six comets, destroying them. Starstriker tries to trigger another comet transformation in Captain Comet. The mutant hero turns Starstriker's attack back on him, causing Starstriker to transform. At the same time, Captain Comet does some psychic reconfigurations in Starstriker's mind. If Starstriker ever tries to uses his powers again, it will trigger another comet transformation, thus ending the menace of Starstriker, once and for all.