Challengers of the Unknown #75

"Ultivac Is Loose!" pits the Challengers of the Unknown against a terrifying threat born from wartime secrets and scientific ambition. When German scientist Felix Hesse pleads for help, claiming his creation—Ultivac—has turned rogue, the team must chase a monstrous robot hand that crashes through the window and snatches him mid-plea. With no time to waste, they’re on the case, determined to track down the runaway machine before it strikes again.

In "Chapter Three: The Fearful Millions," Hesse and Barker seize control of the towering robot Ultivac, turning it into a spectacle displayed at Yankee Stadium. But when Ultivac sends a psychic distress call to June, the machine breaks free—carrying her off into the depths. As Ace tries to negotiate from a jet, the robot’s deadly vibration beam destroys the aircraft. With June trapped inside Ultivac’s dome, the creature plunges beneath the waves, forcing Prof, the master diver, to follow—only to be captured by the robot’s next assault.

In "Chapter Four: The Fatal Prediction!", the Challengers of the Unknown face a chilling dilemma when the enigmatic robot Ultivac, hailed by June as a scientific marvel, unleashes a deadly deception. As Red and Rocky confront the machine, a shocking twist reveals Ultivac’s true intent—only to be upended by a devastating betrayal that leaves Rocky dying, his fate echoing a grim prophecy. With courage and conviction, June steps forward to take Rocky’s place, and in a moment of unexpected grace, the Challengers witness a miracle that alters the course of the robot’s destiny.