Justice League of America #123

In "Where on Earth Am I?", writers Cary Bates and Elliot S! Maggin step out of their usual roles and into the DC Universe itself when they accidentally activate the Cosmic Treadmill left behind by Earth-1’s Flash. Suddenly, Bates is flung to Earth-2 as a powered-up villain, while Maggin lands on Earth-Prime with the Justice League of America—only to find the JSA locked in battle with the Injustice Society, whose members turn out to be something far more unexpected. With art by Dick Dillin and inks by Frank McLaughlin, this 1975 classic blends metafiction with interdimensional intrigue, all capped by Ernie Chan’s dynamic cover.