A â€œfanatic scientistâ€ of Kandorâ€”â€the only surviving city of lost Kryptonâ€â€”who constructs a gigantic â€œenlarging-ray projectorâ€ to accomplish the long-hoped-for enlargement of the city, unaware that his enlarging apparatus contains a â€œfatal drawbackâ€ that will â€œbring doomsdayâ€ to the entire city and its populace by weakening the bonds between the cityâ€™s atoms and causing it to disintegrate completely after only three hoursâ€™ time.
Aware of the fatal danger inherent in Than Olâ€™s enlarging process but helpless to prevent the head strong Kandoriansâ€”who have become convinced that Supermanâ€™s opposition to their plan stems only from petty personal jealousyâ€”from using the flawed ray projector to enlarge their tiny city, Superman barely succeedsâ€”with the aid of Jimmy Olsen, Nor-Kan, Van-Zee, and the Superman Emergency Squad, in reducing the city back to its former lilliputian size with the aid of a â€œshrinking rayâ€ confiscated from Brainiac just as the three-hour time limit elapses and the cityâ€™s buildings begin to disintegrate and collapse, just as Superman had warned.
â€œ... I vow that Iâ€™ll never cease trying to find a safe way to make you normal!â€ announces Superman to the now-remorseful Than Ol and his fellow Kandorians I promise that some day Kandor will become big again, and will stay so forever!â€ (S No. 158, Jan 1963: â€œSuperman in Kandorâ€ pts I-IIIâ€” â€œInvasion of the Mystery Super-Men!â€; "The Dynamic Duo of Kandor!â€; â€œThe City of Super-People!â€). Superman and Jimmy Olsen adopt their alternate Kandorian identities of Nightwing and Flamebird for the very first time during the course of this adventure.