Cover: Joe Shuster & Paul Cassidy

Action Comics #21

Feb 1940 · DC · 0.10 USD

📊 ~46,475 copies sold its debut month

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“The Atomic Disintegrator”

In "The Atomic Disintegrator," Ultra learns of Terry Curtis's groundbreaking invention and sets his sights on claiming it—fueling his ambition to expand his grip on global power. Written by Jerry Siegel and brought to life by Joe Shuster’s bold art with inks by Paul Cassidy, this 1940 issue captures the early days of Superman’s world with a pulse of Cold War-era sci-fi dread. The cover by Joe Shuster and Paul Cassidy perfectly frames the tension, hinting at the dangerous device at the heart of the story.

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writer Jerry Siegel · artist Joe Shuster · inker Paul Cassidy · cover Joe Shuster, Paul Cassidy

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Cast · 15 characters

Bob Daley Chuck Dawson Clip Carson Fog Fortune Gargantua T. Potts George Taylor Gunner Bill Pep Morgan Superman Terry Curtis Tex Thomson The Ultra-Humanite Tong Whistler Will Zatara

Full credits

writer Jerry Siegel

artist Joe Shuster

inker Paul Cassidy

cover pencils Joe Shuster

cover inks Paul Cassidy

Full plot ⚠ may contain spoilers

▸ Reveal full plot — may contain spoilers

Ultra hears of the invention by Terry Curtis of an atomic disintegrator he has created and vows to get it, all in order to further advance his plan to dominate the world.

Plot details indexed by the Grand Comics Database (CC BY-SA).