Battlestar Galactica is a 2004 American military science fiction television series, and part of the Battlestar Galactica franchise. The show was developed by Ronald D. Moore and executive produced by Moore and David Eick as a re-imagining of the 1978 Battlestar Galactica television series created by Glen A. Larson. The pilot for the series first aired as a three-hour miniseries (comprising four broadcast hours in two parts) in December 2003 on Sci Fi, which was then followed by four regular seasons, ending its run on March 20, 2009.

Battlestar Galactica follows a group of human survivors fleeing the destruction of their homeworlds aboard the titular spacecraft, searching for a new home while being pursued by the Cylons, a fearsome society of robots intent on exterminating all humans. Biological models of Cylons, indistinguishable from humans, have infiltrated what remains of the human population, and their identities are revealed over the course of the series.

Main cast + Performer Character Seasons 1 2 3 4 Credited during opening sequenceEdward James OlmosWilliam Adama colspan="4" Mary McDonnellLaura Roslin colspan="4" Katee SackhoffKara "Starbuck" Thrace colspan="4" Jamie BamberLee "Apollo" Adama colspan="4" James CallisGaius Baltar colspan="4" Tricia HelferNumber Six colspan="4" Grace ParkSharon "Boomer" Valerii / Sharon "Athena" Agathon / Number Eight colspan="4" Credited after opening sequenceMichael HoganSaul Tigh colspan="4" Aaron DouglasGalen Tyrol colspan="4" Tahmoh PenikettKarl "Helo" Agathon colspan="4" Kandyse McClureAnastasia Dualla colspan="4" Paul CampbellBilly Keikeya colspan="2" colspan="2" Alessandro JulianiFelix Gaeta colspan="4" Sam WitwerAlex "Crashdown" Quartararo colspan="2" Nicki Clyne Cally Henderson colspan="3" Michael TruccoSamuel Anders colspan="2"

Main characters

William Adama

William Adama, portrayed by Edward James Olmos, is the commanding officer of the Battlestar Galactica and military leader of the Colonial Fleet of survivors after the Cylon attack on the Twelve Colonies. A veteran of the First Cylon War, during which his call sign was "Husker", Adama has the longest tenure as the highest-ranking officer in the Colonial Fleet after the Fall of the Twelve Colonies.

Laura Roslin

Laura Roslin, portrayed by Mary McDonnell, is the President of the Twelve Colonies. Serving as the Secretary of Education at the time of the Cylon attack, she is promoted to president with the deaths of everyone before her in the line of succession. Roslin becomes a religious figure to some in the Fleet, essential to the fulfillment of a prophecy that the refugees will find the mythical planet Earth.

Kara Thrace

Kara Thrace (call sign "Starbuck"), portrayed by Katee Sackhoff, is a gifted Viper pilot, with a volatile attitude that has hindered her career in the Colonial Fleet. However, William Adama has confidence in Thrace's military skills, and she greatly aids the Fleet inside and out of the cockpit.

Lee Adama

Lee Adama (call sign "Apollo"), portrayed by Jamie Bamber, is a former Colonial Fleet Reserve officer who is appointed Galacticas CAG (Commander of the Air Group) after the Cylon attack. The son of William Adama, Lee is a skilled Viper pilot.

Gaius Baltar

Dr. Gaius Baltar, portrayed by James Callis, is a brilliant scientist who unintentionally aids the Cylons in their attack on the Twelve Colonies. A charismatic genius and womanizer, he is initially portrayed as a self-serving opportunist, but becomes a braver and more caring character over the course of the series.

Number Six

Number Six, portrayed by Tricia Helfer, is a female humanoid Cylon model whose copies play several key roles in Cylon society. The copy dubbed "Caprica Six" is considered a hero for her infiltration of the defense systems of the Twelve Colonies, which facilitated the cataclysmic Cylon attack. Developing emotions and an affinity for humans, Caprica Six ultimately turns against other anti-human models and seeks peace between Cylons and humans. The Sixes are stunningly beautiful and typically use seduction as a tactic. They are deeply religious, and tend to feel sympathetic toward humans. Other prominent Six copies include Shelly Godfrey, Gina Inviere and Natalie Faust.

Number Eight ("Boomer" and "Athena")

Number Eight, portrayed by Grace Park, is a female humanoid Cylon model. Two prominent Number Eight copies serve at different times as Galactica pilots: Sharon Valerii, call sign "Boomer", and Sharon Agathon, call sign "Athena". Boomer is a sleeper agent and initially unaware she is a Cylon. She is loyal to Commander Adama but has been preprogrammed as a saboteur, and her true nature is only revealed when she attempts to assassinate him. Killed on the Galactica and resurrected among the Cylons, Boomer subsequently has trouble integrating with both humans and Cylons. She ultimately aligns herself with the anti-human faction of Cylon models led by John Cavil, opposing Athena and the other Eights. Athena poses as Sharon Valerii for an unsuspecting Karl Agathon to help him escape Caprica, and subsequently falls in love with him while trying to earn the trust of the Galactica crew. She becomes pregnant with the first viable hybrid human-Cylon child, and sides with the humans and sympathetic Cylons against the Cavil faction and Boomer.

Saul Tigh Colonel Saul Tigh, portrayed by Michael Hogan, is Galactica XO (Executive Officer) and William Adama's second-in-command. A gruff militarist with an alcohol problem, his relationship to civilians and those under his command is often strained. One of the leaders of the human Resistance against the Cylon occupation on New Caprica, he is jailed and tortured, which embitters him even more. In the season three finale "Crossroads", Tigh learns that he is one of the Final Five Cylons.

Nicholas Bigelow of Screen Rant called Tigh "a deeply flawed yet compelling character", noting that his transformation from a troubled man to a pivotal leader against the Cylons, and the life-altering revelation of his own Cylon nature, make him "a captivating study in imperfection". Screen Rant Craig Elvy wrote that Tigh's best moment of character development in the series was the death of his troublesome wife Ellen at his hands, though it was later rendered "meaningless" by her resurrection.

Galen Tyrol Galen Tyrol (often called "Chief"), portrayed by Aaron Douglas, is the Galactica highest-ranking non-commissioned officer and in charge of maintenance of the Vipers and Raptors. He has a secret relationship with Lieutenant Sharon "Boomer" Valerii. The revelation of her true identity as a Cylon plunges him into crisis. Tyrol later marries and starts a family with Cally Henderson, though it is later revealed that she had had an affair with Brendan Constanza and the child is his. On New Caprica, he is union leader and later one of the leaders of the human Resistance against the Cylon occupation. In the season three finale "Crossroads", Tyrol learns that he is one of the Final Five Cylons.

Screen Rant wrote that Tyrol stands out thanks to "complex relationship with Sharon Valerii and his quest for redemption", which "highlights the show's theme of breaking the cycle."

Karl Agathon

Karl Agathon, portrayed by Tahmoh Penikett, is an Electronic Countermeasures Officer and has the call sign Helo, is part of a two-person Colonial Raptor crew based on the Battlestar Galactica, and is paired with Sharon "Boomer" Valerii before the Cylon destruction of the Twelve Colonies. Stranding himself on the devastated planet Caprica so that Dr. Gaius Baltar can be rescued, he is unaware that Sharon is a Cylon model known as Number Eight, and subsequently falls in love with another copy of Sharon.

Anastasia Dualla Anastasia "Dee" Dualla, portrayed by Kandyse McClure, is a communications NCO working in the CIC on board the Battlestar Galactica. She begins dating President Laura Roslin's aide Billy Keikeya, but eventually cheats on him with Viper pilot Lee Adama. Billy sees them together and confronts Dee, soon after which they are among a group held hostage by terrorists. Billy intervenes when Dee is about to be executed, saving her life and sacrificing his own. Dee pursues her relationship with Lee, eventually marrying him when the Fleet settles in New Caprica. The marriage is tested by their conflicting political beliefs and Lee's affair with Kara Thrace, and they eventually separate. In the uncertainty after discovering the radiation-soaked former home of the colonies, she commits suicide.

Billy Keikeya Billy Keikeya, portrayed by Paul Campbell, is Roslin's Chief of Staff after the Cylon attack, and is one of the few people she considers family. He dies in a shootout during a hostage situation on the luxury liner Cloud Nine in the season two episode "Sacrifice".

Felix Gaeta Felix Gaeta, portrayed by Alessandro Juliani, serves as tactical officer on the Battlestar Galactica during the destruction of the Twelve Colonies and the ship's escape from the Cylons. When the human survivors settle on New Caprica, Gaeta becomes Chief of Staff to new President Gaius Baltar. After Baltar submits to the occupation of invading Cylons, Gaeta is perceived as a Cylon collaborator, but he is a spy for the Resistance. Gaeta is shown to be in a romantic gay relationship with Lieutenant Hoshi of the Pegasus in the web series Battlestar Galactica: The Face of the Enemy. After several Galactica crew members are revealed to be Cylons and having been betrayed by a Number Eight Cylon copy he trusted, Gaeta joins Tom Zarek in a mutiny attempt against Adama's leadership. Their plan is foiled, and Gaeta and Zarek are executed.

Gaeta is depicted as bisexual. Co-executive producer Jane Espenson said that Gaeta is completely "out" to his crew, but explains that they would not have that concept, as it is not an issue in their world. She defines him as "someone free of labels, who has probably had a number of relationships, mostly with males."

Alex "Crashdown" Quartararo Alex Quartararo (call sign "Crashdown"), portrayed by Sam Witwer, is a Raptor Electronic Countermeasures Officer from the destroyed Battlestar Triton who joins the Galactica crew. A member of a three-Raptor survey party sent to examine the planet Kobol in "Kobol's Last Gleaming", Crashdown takes command of a small group when his Raptor is shot down. His inept and life-threatening leadership of the group ends when Baltar shoots him before he can shoot Cally in "Fragged".

Cally Henderson Cally Henderson, portrayed by Nicki Clyne, is a Galactica deckhand. She and Tyrol marry and have a son, Nicholas. Upon learning that Tyrol is a Cylon, she attempts suicide with her child, but is stopped by Tory Foster, who then murders her and saves Nicholas. It is later revealed that she had had an affair with Brendan Constanza and the child is his.

Samuel Anders

Samuel Anders, portrayed by Michael Trucco, is a well-known athlete with the Caprica Buccaneers who forms a resistance group on Caprica with his teammates, where they are stranded after the Cylon attack. He is later a leader in the human Resistance against the Cylon occupation of New Caprica. He eventually trains as a Viper pilot with the call sign "Longshot". In the season three finale "Crossroads", Anders learns that he is one of the Final Five Cylons, ultimately becoming a Cylon Hybrid to guide the Galactica.

Recurring