The Legion of Doom are attempting to use space satellites to freeze the Earth's oceans, creating more land mass at the coastal regions for which they own. The JLA quickly arrive and the two teams engage in a classic battle of wills. This clash leads to Lex Luthor becoming trapped in a glacier of ice.
In the 31st century Legion of Superheroes trainees; Dawnstar and Karate Kid are tasked with minding the Legion's museum. Their tour leads them to Lex Luthor's memorial; his body still encased in a large chuck of ice discovered in the 29th century. Karate Kid Inadvertently frees Luthor who secretly explores the museum himself, and soon uncovers the shrine to his greatest nemesis Superman. There he learns of the Kent's involvement in Kal-El's discovery.
Luthor following the voices of Dawnstar and Karate Kid takes possession of an hourglass which holds the Time Trapper within. Whoever holds the hourglass controls this entity who is the master of time. Luthor returns to the 21st century, but not without the young Legionaries close behind.
The Legion of Doom regroups with a new plan in place; they will prevent the Kent's from ever raising Kal-El, and with no Superman the JLA will cease to exist as well. The JLA arrive but Luthor's efforts prove to be successful, and the Time Trapper causes the time paradoxes to vanish from this reality.
Now it's up to Dawnstar and Karate Kid to stop Luthor's plans for worldwide dominance. They find a loophole freeing the Time Trapper from Luthor's control, but now nothing is preventing him from wrecking chaos throughout reality. The JLA return, but well their power combined with Dawnstar and Karate Kid prove to be enough to stop this new menace, or has our time just run out?