Superman made a journey into the bottle city of Kandor, an interdimensional prison he had liberated from an alien jailer named Tolos. Superman, accompanied by the Atom, hoped to bring peace to the city, which had been in the throes of civil unrest since Tolos' defeat at the hands of the Man of Steel.

Unfortunately, Tolos was not dead, as Superman had hoped. Indeed, he had secreted himself in the bottle city, and when Superman arrived, Tolos took over the Last Son of Krypton's body. Superman was, however, able to use his electrical powers to trap Tolos forever in the energy barrier that served as Kandor's prison walls.

Superman assured the residents of Kandor that Tolos was truly defeated this time, and that they need not fear him. He renewed his promise to help find a way to restore the city and its residents to their proper dimension.

But first, Superman had to deal with the Millenium Guard...