Astounding Stories #36

NoMan infiltrates a Nevada research facility alongside Thunder Courier Linda Rogers to investigate sabotage—but discovers that Linda's own father, Dr. Tim Rogers, is actually an android under the control of a mysterious mastermind. When NoMan's invisibility powers are exposed, he must outwit an army of synthetic stand-ins designed to replace key personnel, all while protecting the truth from Linda and uncovering who's really pulling the strings.

When T.H.U.N.D.E.R. discovers that their ranks have been infiltrated by android duplicates controlled by a villain known as the Mastermind, the team scrambles to identify which agents are real—but the enemy's plan runs far deeper than anyone realizes. As the heroes race against time to stop the android threat, they must confront a perfect mechanical copy of their most powerful member, wielding all the strength of the legendary Thunderbelt. With T.H.U.N.D.E.R.'s Nevada facility under siege and their defenses crumbling, Dynamo and his allies face their most personal and dangerous mission yet.

In "He Wore a Black Beard," a man living with an inventor is thrown off balance when a visitor claims to be from the future. As tensions rise, he hatches a plan to frame the inventor with the visitor’s help—only to realize too late that the time traveler is the inventor’s own future self, and the man’s scheme is a loop he can’t escape.

Dynamo faces off against a mysterious android enforcer when the Council of Warlords—led by the Overlord—seizes a government thorium mine and springs an ambush designed to neutralize the hero's legendary belt. Trapped underground with the Golem and facing execution, Dynamo must outwit both the android's crushing strength and the Warlords' schemes to survive—all while calling in backup from fellow T.H.U.N.D.E.R. agent Menthor. It's a tense subterranean battle where quick thinking and teamwork are the only weapons that might turn the tide.

In "It Waits Under the Sea!" from Astounding Stories #36 (1968), a lone diver ventures into the deep with a daring global journey in mind—only to be lured by a mysterious underwater tunnel. Drawn in by the unknown, he finds himself trapped in a hidden holding tank, sealed away beneath the sea until the next time the exhibit is opened.

NoMan pursues Demo, the master of the sub-men who has eluded Thunder Agents capture and sworn revenge—but when the invisible android tracks his quarry to a hidden cavern base, Demo seizes an unexpected advantage: NoMan's own invisibility cloak. Trapped underground with dynamite, sabotaged equipment, and a desperate enemy who's turned the hunter's greatest tool against him, NoMan must outthink an opponent who now understands his every secret.

In "The Replacement!", a desperate criminal steals a dying man’s jacket and discovers an airline ticket inside—only to find himself aboard a plane with no crew and no other passengers. As the aircraft lifts off into the unknown, his panic grows with every empty seat and silent cockpit. When the police later find his body in a field, the man he stole from is miraculously alive, having escaped death by chance.

Lightning races to prevent sabotage at a T.H.U.N.D.E.R. aircraft test center, only to discover that Baron Von Kampf has forced an insider to destroy the experimental Thunder Jet with his deadly dust weapon. When the agent reveals the Baron is holding his daughter captive, Lightning vows to help rescue her and stop the villain once and for all. Now the speedster must infiltrate one of the Baron's hidden fortresses and face off against a foe who's been waiting for another chance at revenge.