Number Four
the Cylon physicians
Number Four, also known as Simon O'Neil, was a model of humanoid Cylon created by the Final Five after the Cylon War. Often serving as doctors and medics, the Fours sided with the Ones and Fives during the Cylon Civil War.
Number Four, also known as Simon O'Neil, was a model of humanoid Cylon. The model was developed after the end of the Cylon War by the survivors of the Thirteenth Tribe known as the Final Five, following their first humanoid model, Number One. The Fours were the Cylons' medical specialists and frequently took up medical roles, working as doctors and physicians among both human and Cylon society. (Battlestar Galactica, "The Farm", "No Exit"; Battlestar Galactica: The Plan)
Origins and nature#
The Number Four model was developed by the Final Five, survivors of the Thirteenth Tribe, after the end of the Cylon War, following their first humanoid model, Number One. As with the other humanoid Cylons, many identical copies existed, and a Four killed within range of a Resurrection Ship downloaded into a new body with its memories intact through Resurrection. Fours spoke calmly, leaned on logic and were less religious than most of their fellow Cylons. (Battlestar Galactica, "No Exit", "Torn", "Downloaded")
During the Cylon Civil War, the Fours sided with the Number Ones and the Number Fives. (Battlestar Galactica, "Six of One")
Known Fours#
One Four, Simon O'Neill, infiltrated the refugee fleet as a married man, living with his wife Giana and her daughter after the Fall of the Twelve Colonies. He had come to love them, and when a Cavil hidden in the fleet ordered him to blow up the ship they lived on, he agreed only if his family were spared. Cavil refused. Simon left a suicide note and airlocked himself while out of Resurrection range, so his death was final. Galen Tyrol later comforted Giana by pointing out that Simon had killed himself rather than harm the fleet. (Battlestar Galactica: The Plan)
Another Four lived on Caprica as the doctor of the Caprica Buccaneers Pyramid team and stayed with Samuel Anders's resistance after the Fall. Unable to act openly without blowing his cover, and frustrated that the Cavil among them wouldn't give away the resistance's location, he quietly undermined them by handing out too much morpha and contaminating their anti-radiation medication. He was exposed when the resistance killed another Four during Kara Thrace's rescue and recognised the face, and Anders sent Jean Barolay back to kill him. (Battlestar Galactica, "The Farm"; Battlestar Galactica: The Plan)
At least two Fours worked at the Cylon farm where Lieutenant Kara Thrace was taken after being shot. One, calling himself Simon, posed as a human doctor, tried to talk her into bearing children, and operated on her ovaries without her permission. When he slipped and used her call sign, she realised he was a Cylon, killed him and escaped. Another Four intercepted her outside, and the resistance gunned him down as they stormed the building. (Battlestar Galactica, "The Farm")
Frequently asked questions
- Who is Number Four in Battlestar Galactica?
- Number Four, also known as Simon O'Neil, was a model of humanoid Cylon created by the Final Five after the Cylon War. The Fours frequently took up medical roles, working as doctors and physicians among both human and Cylon society.
- When was the Number Four model created?
- The Number Four model was developed by the Final Five, survivors of the Thirteenth Tribe, after the end of the Cylon War. It followed their first humanoid model, Number One.
- Why was there little individuality among the Fours?
- Many identical copies of the Four existed. Like other humanoid Cylons, a Four killed within range of a Resurrection Ship downloaded into a new body with its memories intact.
- Which side did the Fours take in the Cylon Civil War?
- During the Cylon Civil War, the Fours sided with the Number Ones and the Number Fives.
- What did the Four at the Delphi Convalescent Institute do to Kara Thrace?
- At least two Fours worked at the Cylon farm where Lieutenant Kara Thrace was held. One posed as a human doctor and operated on her ovaries without her permission, and Thrace killed him when she realised he was a Cylon.
Sources
- EpisodeBattlestar Galactica, "The Farm", Season 2, Episode 5 (2005)
- EpisodeBattlestar Galactica, "Downloaded", Season 2, Episode 18 (2006)
- EpisodeBattlestar Galactica, "Torn", Season 3, Episode 6 (2006)
- EpisodeBattlestar Galactica, "Six of One", Season 4, Episode 2 (2008)
- EpisodeBattlestar Galactica, "No Exit", Season 4, Episode 15 (2009)
- FilmBattlestar Galactica: The Plan, Television film (2009)
Spotted a factual error or a primary source we missed? Email a correction. Every flagged claim gets reviewed.
Followed from this entry
Cylon
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Simon O'Neill
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Which Cylon Are You? Take the Battlestar Galactica Quiz
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