David Dorman travels across the world to be with his fiancée, singer Olivia St. James. The Justice League begins to suspect the Treasurers’ motives, and the aliens’ cure for the X-Element crisis proves worse than the disease, as one-third of all humans and animals are transformed into monsters. The Phantom Stranger appears to help out, even as Truthspeaker, a rebel Treasurer, reveals that his fellow aliens are actually the first wave of an invasion of Earth by the reptilian War-Kohn.
Faced with the destruction of the Earth, the governments of the world have agreed to barter with the alien Treasurers. In exchange for the vital "X" Element, the Justice League of America have provided the Treasurers with several, seemingly, innocuous items. When the United States Government also hand over a postal carrier, George Arthur Stuart, the Justice League of America cry foul. Stuart, however, convinces the Justice League of America that he is honored to have the chance to save the entire world. A physicist, Dave Dorman, commandeers an airplane, and sets off for Sweden.
Fearing deception, the Atom, the Black Canary, the Green Arrow, the Green Lantern, and Superman decide to, surreptitiously, follow the Treasurers back to their home world. The Red Tornado carries the sphere, filled with the vital "X" Element, into the stratosphere. Before the Red Tornado quite reaches his destination, the sphere explodes. The Batman, the Elongated Man, the Flash, and Wonder Woman look on, in horror, as the Red Tornado falls to his death. Putting the Bat-Plane into a power dive, the Batman closes on the Red Tornado.
The Elongated Man stretches past all of his limits to catch the Red Tornado, suffering severe injuries. The "X" Element disperses across the globe, falling to Earth as rain. Humanity breathes a collective sigh of relief, as the "X" Element resolves all crises, planet wide. On the streets of Stockholm, however, Pop Star, Olivia St. James, witnesses the "X" Element transforming beasts, and men, into monsters. The Justice League of America arrive on the Treasurers' world. From afar, the Green Lantern, and Superman, watch the Treasurers turn Stuart over to another, more hostile, race of aliens, the War-Kohn.
Before the Justice League of America can take action, they are stopped by a Treasurer, known as the Truthspeaker. The Flash is at a loss to effect repairs on the Red Tornado. The Hawkman informs the Justice League of America of the horrific transformations occurring across the Earth. The War-Kohn fire on the Justice League of America's satellite headquarters. Believing the Justice League of America to be destroyed, the War-Kohn commander, Karvus-Kun, orders his ships to descend on Earth. In reality, Aquaman has activated a sensor-deflector, to trick the aliens into believing all systems, aboard the satellite, have ceased functioning.
The Phantom Stranger appears aboard the satellite, offering his aid in the coming crisis. The Truthspeaker reveals the secret history of the Treasurers, and their alliance with the barbaric War-Kohn. Years earlier, the Treasurers, in good faith, had bartered with the War-Kohn, providing them with heat crystals to prevent a coming ice age. When the Treasurers asked for their payment, the War-Kohn refused, threatening violence. The Treasurers entered into a partnership with the War-Kohn. The Treasurers provided the War-Kohn with weapons, and vessels, with which to conquer worlds, in return for a percentage of said world's resources.
The Treasurers sought out worlds on the verge of losing their "X' Element. The "X" Element provided by the Treasurers contained a mutagenic property, one which would convert one-third of the planet's lifeforms into War-Kohn soldiers. The Justice League of America storm the vault, where the War-Kohn are holding Stuart. While the Atom picks the vault's lock, the Justice League of America fight a desperate battle against the War-Kohn. Dorman lands in Stockholm, and fight his way through War-Kohn soldiers, desperate to be re-united with James.