Lex Luthor is an evil genius and Superman's greatest enemy. He wears an indestructible battle suit of his own design. Luthor engineered nanobots designed to feed on the solar radiation in a Kryptonian body, namely Superman's, and called it Repulse. The Repulse would replicate into the millions and produce a geometrically increasing repulsive electromagnetic charge. Everything around Superman would be repelled and he would be a constant danger. Luthor coated himself in Repulse and roamed the streets of Metropolis to lure Superman into battle. Superman, Wonder Woman, and Hawkman responded. Eventually, Superman cut a hole in the street with heat vision and Luthor fell into the sewers. He returned to his underground lair but was followed by Superman. Superman grabbed Repulse and realized it was Luthor all along. Luthor was turned over to the police and incarcerated at Stryker's Island Penitentiary. Superman was overcome by the Repulse and flew into space.
Wonder Woman and Hawkman went to Stryker's and demanded to know how to save Superman. Luthor claimed he didn't know what they were talking about. Hawkman dispensed with formalities and pulled off a section of the prison door. Wonder Woman stepped in and slammed Luthor against the wall then tied him up in the Lasso of Truth. She asked again. Luthor was compelled to tell the truth and explained what his Repulse was then theorized something more powerful than the Sun could drain off the power of the nanobots. Wonder Woman and Hawkman took Luthor with them on Justice-1 and flew to Black Hole XT-357. While they watched Superman flew near the black hole's event horizon and drain the Repulse, Luthor rescaped his restraints and hijacked Justice-2. He opened fire on Superman in an effort to push him into the black hole. However, a meteor collided with Justice-2 and sent Luthor flying towards the black hole. Superman went after Luthor. Luthor marveled at seeing the center but knew the Repulse's protection wouldn't last. Superman saw the Lasso of Truth and grabbed hold. Wonder Woman pulled them out. The last of the Repulse drained off. Luthor realized the Repulse was still operating in the collapsing black hole and advised a quick departure. Soon after, a massive explosion was triggered. Luthor was returned to prison and Superman was medically cleared.