Appleton was an investigator during the Galactic Civil War, specifically a Human Imperial Major of male gender. Following the Battle of Yavin, he received orders to retake the Star Destroyer known as the Blackguard. The ship had been seized by Captain Andal Sait, an Imperial officer who had betrayed the Empire and declared himself a Grand Admiral.
In the 2003 Star Wars Galaxies video game, Appleton appeared as a non-player character. This massively multiplayer online roleplaying game was created by Sony Online Entertainment and distributed by LucasArts. The game shut down on December 15, 2011. Appleton's character was included in the game when the "Star Destroyer" Heroic Encounter was released as part of the "Chapter 8" update on November 1, 2007.