Sharon Valerii

Number Eight Sharon "Boomer" Valerii Sharon "Athena" Agathon
Battlestar Galactica character
First appearance	Miniseries
Last appearance	Battlestar Galactica: The Plan
Portrayed by	Grace Park
Information
Aliases	Boomer, Athena
Species	Humanoid Cylon
Gender	Female
Title	Lieutenant Junior Grade
Colony	Cylon Homeworld, claims to be from Aerelon's colony Troy
Affiliation	Colonial Fleet/Cylons

Number Eight is a female humanoid Cylon model on the television series Battlestar Galactica, a reimagining of the classic show of the same name. She is portrayed by Grace Park. Two prominent Number Eight copies serving as Galactica pilots are Sharon Valerii and Sharon Agathon, using the call signs "Boomer" and "Athena", respectively.

Cylon models Six and Eight are the most common in the series. Many Number Eight copies have been seen in various roles, including leadership positions; two are featured as central characters — Boomer and Athena.

Lieutenant Junior Grade Sharon "Boomer" Valerii is a Cylon sleeper agent programmed to believe she is human. For example, she has been implanted with false memories of being raised on Troy by her parents Katherine and Abraham Valerii, who supposedly died in an accident killing all the members on the mining colony. Whether or not Katherine and Abraham actually existed is unknown. In the time before the mini-series, Boomer and Galen Tyrol are romantically involved, although their relationship is against military protocol (she is an officer, he's enlisted). Due to her programming, she performs a number of sabotage actions (including bombing the Galactica's water tanks) but has no conscious memory of these actions; although,in the special entitled The Plan, we learn that she had a Cylon handler, Brother Cavil, who activated her missions & chastised her for allowing human weakness (inability to hold her breath long enough) to prevent her from planting all the explosives in the water tanks; & later, for not shooting Adama in the head. Tyrol trusts her and hides evidence implicating her in the water bombing but later suspicious events cause him to break off his relationship with her. In time, she begins to suspect something may be wrong with her. She asks Gaius Baltar to administer a blood test to determine whether she is a Cylon. Although his test demonstrates she is in fact a Cylon, he decides not to inform her or anyone else, out of fear she will kill him. She is relieved for a while but gradually her suspicions return and she attempts suicide. Her programming, however, prevents her from killing herself.

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