Action Comics #277

In "The Conquest of Superman!", a stranded alien named Stålmannen faces a crisis when a damaged plane carrying a hydrogen bomb can't land on his home planet. With no other choice, Earth's government turns to the imprisoned Lex Luthor, who saves the plane—only to escape and launch a daring scheme to steal Fort Knox. Using a machine that fires kryptonite-tipped balls to trap Superman, Luthor believes he's triumphed, boasting that he’s outsmarted the Man of Steel. But when he learns the truth from the news—his victory was over just a robot duplicate—his grand plan crumbles. The story unfolds with a mix of classic sci-fi tension and Luthor’s cunning, all centered on a moment of hubris that unravels before it’s even complete.