Malevolent Manipulating Mental Masterminds

Mustached masterminds of the mind, exerting their knowledge to create a new form of man. Each used their genius in different ways. While Hector Hammond of Earth-One used this gifts for greed, Chuck Grayson of Earth-Two chose to use his gifts for good. Both tapped into harnessing the brain and extending life.

Hector Hammond was a criminal who stumbled upon a strange iron ore meteor that could mutate the minds of men tens of thousands of years advanced. At first using four scientists, whom Hammond had kidnapped and mutated in order to provide him futuristic inventions, after a battle with the Green Lantern he found his plans quashed. Hector then used the meteorite on himself, gaining telekinetic power and immortality, although the process had debilitating effects on his body.

Chuck Grayson was the research assistant of Robert Crane, both pioneers in the fields of cybernetics in the early 1940's. When mobsters shot Crane in his laboratory, leaving his body dead, Grayson struck upon the idea of transplanting his friend's brain into the robot body they has built together. As Robotman, Crane cleared Chuck of a murder charge for his death, capturing the culprit. Soon after the criminal Murder Master had temporarily brainwashed Chuck into attacking Paul Dennis, his pal Robotman's alter ego. Later, the female Ultra-Humanite tried to force Grayson into transplanting her brain into Robotman's body, but failed.

Hammond suffered a side effect of immobility, driving him to find a cure for his interminable condition. Hammond continued to also scheme while tormenting Lantern and his Justice League allies repeatedly over the years. Although he was paralyzed, Hammond was able to manipulate others mentally to do his bidding including Sonar, the Shaggy Man and others villains. Eventually, he created a new incarnation of his old ally Amos "Mr. Memory" Fortune's Royal Flush Gang as the Wildcard, using a robotic Ace to lead them. Later, he joined forces with his ex-girlfriend Carol Ferris in her Star Sapphire identity versus their adversary Green Lantern.

Chuck continued his own work in the robotics field alongside Paul Dennis, and later as a resident scientist. On one occasion, the pair were attempting to rebuild a future robot known as Mekanique, whom the All-Star Squadron viewed as a danger and dispatched Green Lantern and other members to capture. Later, Chuck joined the secret American government agency known as Project M, a facility where Grayson built the G.I. Robots to be used in field operations on the Pacific islands during World War II. While Crane journeyed to Earth-One to aid his old friend Steel who had migrated there, Grayson remained behind. Soon afterwards, learning that exposure to radioactive brainwaves projected from the alien Powerstone caused him to have brain cancer, Chuck devised the means to preserve his body. Using cryogenic device to perfectly preserve his dormant body for decades, awaiting Robotman's return to Earth-Two. Unaware of his friend's gift, Robotman tracked down a mobster he'd been pursuing who trapped the hero in a mine shaft for decades. Once revived, Crane discovered that he now had the opportunity to become a human once more, As Chuck Grayson he was reborn, later testifying in behalf of Green Lantern and the Justice Society in court.