Justice League of America #40

In "Indestructible Creatures of Nightmare Island!", the Justice League of America faces a terrifying mystery when a peace machine built by inventor Andrew Helm spirals into chaos, unleashing nightmarish illusions drawn from the heroes' deepest fears. Written by Gardner Fox and illustrated by Mike Sekowsky, with inks by Bernard Sachs and lettering by Gaspar Saladino, this 1965 classic sees the team confronting psychological horrors they can't touch—until they track the source back to the malfunctioning device. The cover by Mike Sekowsky and Murphy Anderson captures the eerie tension of the island's waking nightmare.