John Cavil (Number One) is a fictional character and the main antagonist from the re-imagined Battlestar Galactica television series. He is portrayed by Dean Stockwell. In the fourth-season episode "Six of One", Cavil's model number was revealed as Number One. Background John Cavil, aka Number One, is a humanoid Cylon model that appears as a highly rational, eccentric man in his late-sixties. The Cavils have a heavy sarcastic demeanor and a sense of humor. They take neither religion nor death seriously and are the only atheist Cylon model. A Cavil is first seen aboard the Galactica assuming the role of a priest, offering spiritual guidance, and going by the name "Brother Cavil". A unique characteristic of the Cavils is the sadistic, cruel and Machiavellian streak in their personalities. The Cavils openly mock their fellow Cylons every time they attempt contact with humans, even when it is necessary. Even though they view death as a nuisance, the Cavils are extremely displeased with pain (placing the blame on the Final Five). This view fuels the idea that the Cavils wanted death to the humans to be as quick as possible but were unprepared for the aftermath. Their attitude towards human mortality, rather than irrational hatred, derives from their ignorance about death and its consequences. As revealed on Battlestar Galactica: The Plan, the Cavil that was stationed in Caprica learned from Samuel Anders the motives for the resistance; that humans do not leave anyone behind, even their dead. Respecting their resilience, the Caprica Cavil agrees with Caprica Six and Sharon Valerii (Boomer) to abandon the Colonies. Disappointed with the other Cylon models after failing to accomplish anything through boycott and sabotage, the Galactica Cavil fails to learn any lesson. As they are discovered and airlocked from Galactica, Galactica Cavil swears to "box" Caprica Cavil for his insubordination and is indicated to be the same Cavil that is the main enemy of season four, given his plans to destroy humanity once and for all when he resurrects. It is later implied in the series that the Cavils, akin to their creators, lack superhuman strength and are the least able to defend themselves. It is also implied that the Cavil who led the Civil War and who killed himself in the CIC when he realized he was losing and had no chance of winning, is the resurrected Galactica Cavil. Like the Simons and Number Threes