Gilhooley was a 23rd century Human male. By the 2250s, Gilhooley was serving in Starfleet and was assigned to the USS Farragut, under the command of Captain Garrovick. Gilhooley served aboard the Farragut around the same time as Lieutenant James T. Kirk and the two became friends, often playing three-dimensional chess or sharing various off-color limericks in the ship's lounge in their off-duty hours.