Garron and his younger assistant, Unstoffe, embarked on a career as galactic swindlers, selling planets to unsuspecting victims. In what Garron had promised Unstoffe would be their last mission, Garron tried selling Ribos to the Graff Vynda-K using a lump of jethrik, which turned out to be the first segment of the Key to Time, attempting to create the impression that jethrik was common on Ribos. As a result, the Graff had the idea of mining the valuable mineral and buying an army to help him retake his throne after he was deposed instead of spending years training the people of Ribos whose technology had not discovered higher science for the same purpose.
When the Graff found out the truth, Garron and the Fourth Doctor were forced to work together to escape his vengeance. Garron eventually ended up with the Graff's spaceship, filled with eighteen years of plunder, although the Doctor took the jethrik from him despite Garron's attempt to steal it back using a simple sleight of hand. (TV: The Ribos Operation)