"Superman: "The Atomic Disintegrator"": Now living in the body of movie star Delores Winters, the evil Ultra-Humanite uses his feminine wiles to lure, then abduct, atomic scientist Terry Curtis. Humanite forces Terry to build him an atomic disintegrator, mounts it on an airplane, and uses it to
Action Comics #21 is an issue of the series Action Comics (Volume 1) with a cover date of February, 1940.
Synopsis for Superman: "The Atomic Disintegrator"
Now living in the body of movie star Delores Winters, the evil Ultra-Humanite uses his feminine wiles to lure, then abduct, atomic scientist Terry Curtis. Humanite forces Terry to build him an atomic disintegrator, mounts it on an airplane, and uses it to blackmail the city of Metropolis.
Superman gets involved in all this, partly by accident, when Clark Kent gets blown up in an early test of the weapon, but inexplicably survives, and meets Terry Curtis in the process. Superman defeats the air attack and finds Ultra's secret base, hidden inside a live volcano, but the well-prepared Ultra-Humanite has rigged the city of Metropolis with an atomic explosive device. Ultra blackmails Superman into committing some high-profile super crimes, and to defeat the police and national guard several times in the process, but ultimately Superman is able to destroy Ultra's machinery, rescue Curtis, and blow up the Ultra-Humanite's volcano lair.
Appearing in Superman: "The Atomic Disintegrator"
- Terry Curtis (First appearance)
- several soldiers and policemen
- Ultra-Humanite's Atomic Disintegrator
- Ultra-Humanite's airplane
Synopsis for Pep Morgan: "The Florida Handicap Race"
Pep Morgan travels with Mr. Johns to Florida, to see the horse, White Patch, run in the horse races. A group of gangsters have a lot of money riding on White Patch losing the race, and they aren't kidding around. They try throwing a bucket of acid at White Patch, and then try injecting him with poison. Pep outsmarts the thugs and keeps them from sabotaging the race, but only by tricking them into killing the wrong horse. White Patch goes on to win.
Appearing in Pep Morgan: "The Florida Handicap Race"
- Mr. Johns (Single appearance)
- Jim Riba (Single appearance)
- Joe (Single appearance)
- Pete (Single appearance)
- White Patch (a horse) (Single appearance)
- another horse (Dies)
Synopsis for Chuck Dawson: "Kidnappers"
Chuck Dawson comes across a house belonging to a couple of kidnappers. They are holding a child for ransom, and try to kill Chuck before he can interfere.
Appearing in Chuck Dawson: "Kidnappers"
- Blacky (Chuck's horse)
- Lynch (Single appearance)
- Apache Joe (Single appearance)
- Jack Thatcher (Single appearance)
Synopsis for Clip Carson: "The Gun-Running Racket"
While in Algeria searching for an adventure, Clip Carson saves a man called McCabe from a beating by two robed men. McCabe tricks Clip into smuggling guns to a rebel faction, by using the pretense of delivering crates of food to a hungry camp. On arrival, Clip is imprisoned in one of the rebels' tents, while they inspect the merchandise. Clip knocks out a guard and steals his clothes and sneaks away, then reports the gun smuggling to the Algerian authorities. Then he heads back to McCabe's residence to deliver some justice of his own.
Appearing in Clip Carson: "The Gun-Running Racket"
- McCabe (Single appearance)
- Sheik (Single appearance)
- Tractor Car
Synopsis for Tex Thomson: "The Doll Murders"
Tex Thomson and Bob Daley get involved in a murder case where all the victims received wooden dolls of themselves, depicting the way they will die, unless they follow the written demands. When a doll of himself is left at his doorstep, Tex has limited time to find the killer before he becomes the next victim.
Appearing in Tex Thomson: "The Doll Murders"
- Maurice Oliver (Single appearance)
- Colonel Rushmore (Only appearance; dies)
- Mr. Wendt (Single appearance)
- Tex's Roadster
Synopsis for Three Aces: "The Lost Scot Gold Mine"
The Aces take Tony M'Crea up on her invitation to visit her with her father, Mack. They learn from the older M'Crea that he had been living on land that holds lost gold, ("The Lost Scot", as he calls it), ever since his partner Scottie first announced he found it, years ago. But Scottie went missing by the time Mack returned with men to dig it up, and the treasure was never found. But Jinx, a lowlife scumbag, has recently been trying to force the M'Creas off the land, so he can grab the gold for himself!
Jinx and his men see Tony walking along with Gunner, and so they cause a landslide to try and get rid of the tough young lady. Gunner pulls Tony into a cave beneath the hills to avoid the falling rocks. The landslide barricades the entrance, so they can't go back out, but as they explore the cave, not only do they find another way out, but the Lost Scot gold mine as well!
Appearing in Three Aces: "The Lost Scot Gold Mine"
- Tony M'Crea
- Jinx (First appearance)
- Jinx's men (First appearance)
- Mack M'Crea (Flashback and main story)
- Scottie (Flashback only) (Only appearance; dies)
- Three Aces' planes
Synopsis for Zatara: "The Deaths on the Moor"
In England, Zatara and Tong find a corpse lying in the road on their way to Lord Ralway's manor. When they bring it to the coroner's office, he has Zatara arrested and thrown in jail. Sensing there is more here than meets the eye, Zatara escapes to discover that the coroner and the sheriff are in cahoots in a plot to steal Lord Ralway's fortune. Their murder weapon is a flock of vultures, which they have trained to lift people and drop them from a great height. Zatara magically defeats them.
Appearing in Zatara: "The Deaths on the Moor"
- Coroner (Single appearance)
- Sheriff (Single appearance)
- Ralway's double (Single appearance)
- Sark (Single appearance)
- Lord Ralway (Single appearance)
- Published by Detective Comics, Inc.
- First issue of Sheldon Moldoff art on Clip Carson.
- The Atomic Disintegrator is reprinted in Superman: The Action Comics Archives Vol. 2, and Superman Chronicles Vol. 3, and in Superman:The Golden Age Omnibus Vol. 1 HC.
- This is the Ultra-Humanite's last Golden Age appearance, not counting two single-panel cameos in Superman #17 and #20. The chronologically next appearances of both Ultra and Terry Curtis are in All-Star Squadron #21.
- Tex Thomson:
- Tex's friend Colonel Rushmore who appears in this story is presumably not the same character as the Colonel Rushmore who appeared in Action Comics #13, who turned out to be a criminal and was arrested.
- Also appearing in this issue of Action Comics was:
- "Blaze of Glory" (text story) by Terry Keane
- Pep Morgan reads Action Comics.
- Fred Guardineer signs his Pep Morgan art as "Gene Baxter", and signs his Zatara art as himself.