Sergeant in the United States Marine Corps. Originally stationed at Icarus Base, he was among the evacuees forced to resettle on board the Ancient deep-space vessel Destiny, millions of light years from home.
Spencer evacuated with the rest of the Icarus team to the ninth chevron address during an unexpected attack on the Icarus planet. Spencer had a great deal of difficulty adjusting to the state of affairs aboard the Destiny. He was caught hoarding food and water, nearly assaulted Dr. Franklin in a corridor, and attempted to incite riots against those in charge. He wanted nothing more than to simply get off that ship.
Sergeant Spencer took sleeping pills to help take the edge off, but when they ran out he felt he had nowhere left to go. He took his own life, recording a suicide note on a kino before shooting himself.
Air, Part 1 - Spencer and the rest of the Icarus team escape attack through the Stargate to the Destiny.
Air, Part 2 - Fearing a protracted stay aboard Destiny, spencer hoards food and water for himself.
Air, Part 3 - Spencer joins Lt. James' team in attempting to recover Sgt. Greer and Lt. Scott from the lime planet.
Darkness - Spencer joins a group cornering Eli Wallace for information. He later records a message for the kino.
Light - When 15 personnel have been chosen for the shuttle Spencer tries to start a riot, but he is beaten unconscious by Ronald Greer.
Water - While searching through personnel quarters for ration theft, Greer discovers Spencer has hoarded supplies of food and water.
Justice - Having run out of sleeping pills, Spencer records a suicide message explaining his actions, and ends his life.