All-Star Comics #51

In "Invaders from the World Below! [Part I]," the JSA investigates strange occurrences in Civic City that lead them to Dr. Crillon, a scientist who claims a hidden race of Diamond People beneath the Earth is behind the anomalies at the Bottomless Lake and Old Reliable Geyser. When Crillon and a man named Mr. Exnam vanish mid-presentation, the team uncovers clues in his notebook that suggest a looming threat—and decide to act before it's too late.

In "Invaders from the World Below! Part II," Flash, Wonder Woman, and Black Canary race to the abandoned World's Fair grounds after Crillon's clues point to an imminent attack by the Diamond People. As a sudden volcano erupts on a playground, the heroes fight to contain the lava—only to be blinded by a gem ray and hurled into the smoking crater. Meanwhile, at Bottomless Lake, G.L. and the Atom confront an icy mystery, discovering the lake has frozen over, but their efforts are undone when the Diamond People strike, overwhelming them with the same blinding ray and sending them tumbling over a cliff.

In "Invaders from the World Below! Part III," Dr. Mid-Nite and Hawkman race to a secret government facility only to find it under siege by the relentless Diamond Men. As the duo fend off the attackers, a sudden blast from the Gem Ray leaves them disoriented—just as a mysterious figure steps through the door, claiming to be one of the invaders, Charles Crillon, with secrets that could change everything.