A Kandorian scientist, Than-Ol, convinced the people of the Bottle City of Kandor that Superman knew how to enlarge Kandor but declined to do so, and the Man of Steel was declared an enemy of Kandor.
Superman and Jimmy Olsen shrank themselves, entered Kandor, and assumed the secret identities of Nightwing and Flamebird to prove Superman's innocence, and to show the Kandorians that Than-Ol's enlarging process would make them normal-sized, but will also cause them to be disintegrated.
