Sarko was once a criminal mastermind on Earth named Sappo, who used his powerful hypnotic powers to force others (including Cliff Grant) to commit murder and other crimes for him. Sappo was eventually caught and sent to prison, but somehow, he got away and escaped on a ship bound for the planet Mars. He landed on Mars around August 31, 1933, but after his crew died, he travelled to the dark side of mars where he became the master of a race of one eyed creatures. He intended to use them to conquer the city of Ru, and take the princess as his mate, but he was oppossed by Flint Baker and the men of his Mars expedition. In the fight, Sarko killed Cliff Grant and nearly killed Baker, before he was shot by one of Baker's other men.