The War Between Superman and Jimmy Olsen is a 1959 Superman comic story.
Jimmy Olsen starts acting strange after a visit to the Fortress of Solitude. He also develops Superman's powers. As it turns out, Jimmy has been replaced by El Gar-Kur, a criminal from Kandor who used plastic surgery to alter himself to look like Jimmy. He tries to kill Superman, but is thwarted and returned to Kandor for trial.