Garguax came to Earth from an unknown planet in order to develop and test his highly advanced weaponry. Garguax claimed that he had been banished from his own planet and that he had intended to use his weapons, once perfected, to conquer it. Chief amongst his weaponry were a group of advanced androids called the Plastic Men, an army of superheated, super strong and invulnerable servants. The Plastic Men were not programmed with any personality, making them slaves to Garguax.
After his first defeat by the Doom Patrol, Garguax formed an alliance with the Brotherhood of Evil and General Immortus. Alongside the Brotherhood, Garguax fought the Doom Patrol repeatedly and unsuccessfully.
Finally, Garguax was revealed as an agent of Zarox-13, the ruler of his home planet. The Doom Patrol and the Brotherhood joined forces to defeat Zarox-13 and to foil Gargaux's plan to destroy the Earth. After his defeat, Garguax retreated back to the moon with his Plastic Men.
During the Invasion, Garguax attempts to join up with the allied aliens, but his offer is rebuked. Instead, he joins forces with the Doom Patrol in attempting to protect the Earth. After he double crosses the team, the Chief uses a laser sattelite to shoot down his ship, apparently killing him. However, Garguax is later mentioned as a vice president of corporate affairs of Mr. Somebody Enterprises.