Threepwood was a member of the clone troopers, fighting for the Grand Army of the Republic throughout the Clone Wars. He participated in a search on Christophsis for the escaped Sith Lords Count Dooku and Quinlan Vos, who had broken free from Republic imprisonment, along with his clone comrades Tracker and Boil, and the Jedi Knights Obi-Wan Kenobi and Anakin Skywalker. Threepwood, with his team, investigated the wreckage of the ship Banshee, which Dooku and Vos had hijacked and subsequently crashed. The Jedi and clones concluded that the escapees had lived through the crash, though at least one was injured. Their hunt concluded during the second battle of Christophsis.
Before the novel Dark Disciple was published, a clone trooper named Threepwood appeared in the Nintendo DS edition of Star Wars: The Clone Wars: Republic Heroes.