"It's not enough to survive. One must be worthy of survival."
Played By: Edward James Olmos
An almost-retired Commander whose assignment to the Galactica was a going-away present. As a veteran of the first Cylon war, Bill Adama is actually one of the better choices for command in the second war, not to mention a Cool Old Guy.
A Father to His Men: His troops look up to him, and he cares deeply for them. Ironically, he was probably more distant with his son than the rest of the troops under his command at the beginning of the series.
The Secretary of Education under President Richard Adar (sometimes literally under), Laura Roslin was attending the de-commissioning ceremony on Galactica when the Cylons attacked. 43rd in the line of succession, she was sworn in as the lawful replacement President of the Twelve Colonies. Immediately other characters began to snark about having a kindergarten teacher for a president, but Roslin handled the office with more aplomb than even her supporters could have expected.
Big Good: As President of the Colonies, she shares this role with Adama who leads the military.
Death by Origin Story: Her father and two younger sisters died in a car accident. After grieving for several months, she agreed to become part of Adar's campaign for President as a way to move on. It set everything in motion for her eventual arrival on Galactica.
Fiery Redhead: She is fierce and more than willing to talk back to anyone who questions her.
Iron Lady: She's far more stern than her opposition expects from a "kindergarten teacher."
Our Presidents Are Different: She is definitely President Iron. When pushed too far, she becomes President Action. Her belief in the Pythian prophecies causes some to think of her as President Lunatic. She crosses the line into President Scheming once by allowing her cabinet to fix an election. The plan falls through, however.
An excellent pilot with a rebellious streak a mile wide. This makes her Crazy Awesome, both in and out of the cockpit... though the show also deconstructs just what happens when you have a genuine Military Maverick on your hands. The Cylons, particularly Twos, claim that she has a "special destiny," and ultimately she uses Magic Music to lead the fleet to Earth. ...After dying and being returned as some sort of Angel Unaware.
Cartwright Curse : Zak ends up dead as a result of her passing him through a test he failed, while Sam is first left behind on an irradiated Caprica, then later rendered brain-dead by a bullet to the head. At the very end, when it looks like she finally has the chance to be with Lee, she disappears into thin air, leaving him behind.
The son of Bill Adama, from whom he is estranged due to the death of his younger brother Zak. Apollo's opinion is that Adama pressured Zak into becoming a pilot, which Zak was not ready for; he blames his dad for his brother's death. He also takes after his grandfather (lawyer Joseph Adama) in being rather more loyal to laws, rights and civil liberties than the uniform. Eventually promoted to Commander, put in charge of the Pegasus, and wed to Dee.
The Ace: Lampshaded by his callsign, as Apollo is The Ace in this universe's pantheon.
Badass: Like most of the military cast. Dangerous both in and out of the cockpit.
Cartwright Curse: His pregnant girlfriend gets killed in the Cylon attacks, Starbuck gets married to Anders right after finally admitting she loves him, and before eventually dying, he has a rocky relationship with Dee before separating from her and she commits suicide. Lee is not lucky in love.
Knight in Sour Armor: Lee has a pretty low opinion of many people, constantly calling them out for falling short of their ideals. He is hardest about this on himself. Still, he is probably one of the people in the series who will most reliably choose to do the right thing, no matter how many people he pisses off and no matter how badly he believes it will backfire on him.
Will They or Won't They?: A solid three-and-a-bit season's worth with Starbuck, putting them at the center of a mad-crazy Love Dodecahedron (Starbuck loves both Lee and Anders; Lee loves both Starbuck and Dee; Dee loves both Lee and Billy).
"You have not heard the last! No more Mr. Nice Gaius!"
Played By: James Callis
A genius scientist working on a new navicomputer program for the Colonial military, Baltar was unwittingly instrumental in the Cylon massacre: he was seduced by a Number Six who he believed worked for a competing defense contractor, and gave her access to the program, into which she inserted a virus which managed to disable most of the fleet. Surviving via luck and reputation, Baltar now has to negotiate the fleet while keeping his betrayal secret. There's also the fact that he now holds conversations with his version of a Shoulder Angel, another Six copy. Becomes President on the platform of insisting that the fleet colonize a semi-habitable planet called New Caprica, which turns out to be a huge mistake.
Even Evil Has Standards: It would be a real stretch to call him evil (Though Cowardly and narcissistic are very much fair descriptions). Still, he was absolutely horrified at Admiral Cain's appalling treatment of a Cylon prisoner.
Handsome Lech: He attracts women fairly easily, but he's quite the perv.
Hookers and Blow: The Baltar administration was marked by its groundbreaking lap dance & pill-popping initiatives.
Religious Robot: Inverted; he's a missionary spreading Cylon monotheism to the humans.
The Smart Guy: Initially, he's pretty much the source of science advancement on Galactica.
Took a Level in Badass: He steps up in later seasons until he's part of the Galactica defense team in the finale, repelling the Cylons with an assault gun.
Villain Protagonist, deconstructed: Baltar isn't malicious, just a selfish coward (ie. not a hero like most of the other cast) with the occasional flash of incredible Genre Blindness.
Battlestar Galactica Military
"If the crew doesn't hate the XO, then he's not doing his job."
Played By: Michael Hogan
After Bill Adama was mustered out from the first Cylon war and began serving on a commercial freighter, he met a fellow veteran named Saul Tigh, and the two formed a deep friendship. When reinstated, Adama pulled strings to have Tigh brought in as his second-in-command. Tigh is an alcoholic who is often Off The Wagon, and is probably the series' biggest bearer of Fantastic Racism against the Cylons (with Starbuck as a close second). How amusing, then, that he's one himself.
Achilles in His Tent: After New Caprica, he becomes a drunk wreck for a while. Notably, one script that was written before this was decided had to hastily replace his role with Lee, resulting in Lee looking quite out of character as a hardline anti-Cylon bigot.
Colonel Badass: He's certainly competent, and he serves his role well.
The Creon: Takes command of the Galactica only when Adama is shot, and gives it back immediately as soon as possible. He never plots against Bill Adama for a second, even when he has serious issues with his commander's behavior. He even outright says that it was always supposed to be them leading together, not him leading alone.
The Lancer: To Bill, but is a deconstruction. He is awesome as a second in command, but almost no one (most of all him,) ever wants him to be the number one of the fleet's command. He excels at being Bill's number two, but is completely useless in any other capacity. This is inverted though, when he redeems himself by effectively leading the New Caprican resistance, even if his tactics are... somewhat suspect.
Poisonous Friend: He's kind of hell on Bill's sanity, though he really doesn't mean most of it.
Reincarnation Romance: He and Ellen were married originally too, and somehow found each other again after Cavil wiped their memories.
"All I know is if there is a God, he's laughing his ass off."
Played By: Aaron Douglas
Senior Chief Petty Officer Tyrol is in charge of keeping Galactica's birds flying. He's very much an everyman in his approach to things, and often finds himself in positions of being the Only Sane Man. He was carrying on with Boomer for a while.
A Father to His Men: He cares about his flight crew, and when some had to be sacrificed to put out a fire, he carried bitterness about it for a few episodes.
Ascended Extra: Tyrol was originally intended as a Flat Character, expanding primarily due to Aaron Douglas' ability to throw in dialogue, character names and other useful touches.
Butt Monkey: Things go poorly for him, starting with his girlfriend being a Cylon.
Fake Guest Star: Like Tigh and Helo, he's there from beginning to end, and missed only 7 episodes over the show's run.
Hot-Blooded: Especially on New Caprica, where his speech to the people was modeled after real life labor speeches.
Humiliation Conga: In a very short amount of time, he finds out he's a Cylon, his wife apparently commits suicide over it, he finds out she cheated on him and that his baby isn't even his, and then he learns a former lover actually killed his wife. And then he ruins the Cylon-Human alliance by reacting to that information.
Number Two: As the highest-ranking NCO in the fleet, Tyrol has aspects of this.
"Symbols matter. Uniforms, flags, banners - even mascots. They're like pieces of your heart that you can see."
Played By: Tahmoh Penikett
A Guy in Back in a Colonial Raptor, flying under Sharon "Boomer" Valerii, whom he kind of has a thing for. During the pilot/miniseries, their ship lands on Caprica and Helo abandons his copilot seat to save Gaius Baltar. That was meant to be the end of this Mauve Shirt, but fan reaction to him was so positive that RDM and David Eick decided to keep following his adventures, which involve being rescued by another Sharon copy. With her, he hecomes the father of "Hera," the first human-Cylon hybrid; he also serves as Adama's Number Two while Tigh is stuck on New Caprica.
Ascended Extra: He was supposed to be written out at the end of the miniseries.
Why Do You Keep Changing Jobs?: Since his primary sole is pretty much "The guy who married a Cylon," he's free to take whatever position is needed to be filled for the sake of the episode. He goes from ECM officer on a Raptor, to XO, to "mayor of Dogsville", to XO...
"I started this, and I'll see it through! Now get on that frakking ship!"
Played By: Alessandro Juliani
First appearing as a CIC crewmember, he eventually gets assigned to Dr. Baltar as a personal aide. He's an idealist—which is a bad thing to be in Galactica's World Half Empty; losing his leg in Season 4 is only one link in a "Break the Cutie" chain. Eventually leads a mutiny with Tom Zarek, which they lose.
Bi the Way: Just sort of turns out to be bisexual with no fanfare.
The Cast Show Off: After the producers discovered that Alessandro Juliani is a fully-trained and highly-regarded operatic baritone, they found a reason for him to sing. Shame it was Gaeta having his leg shot half off and then amputated, rather than, say, a morale concert - but still...
A Twofer Token Minority first appearing as a Galactica CIC officer in the miniseries, where she basically played the role of Uhura. Provides possibly the biggest Shocking Swerve in the series when, after a happy and successful date with her ex-husband Lee, and with absolutely no prior indicators, she blows her brains out.
What Could Have Been: she was originally slated to be killed off in an early episode. There seems to be a lot of fans who would have rejoiced in this. Or not, since the things that incur those fans' enmity hadn't happened yet.
From the same class as Kat, Hot Dog evidently flunked out of naval academy before the Destruction. He survives the entire series, eventually maturing into one of Galactica's best and most mature pilots. He's also the Real Life Apollo, as he is played by Bodie Olmos, EJO's son.
Ascended Extra: Originally just "new meat" but he winds up an important part of the Galactica's defense.
In-Universe, Apollo acknowledges him taking a level when he takes his own wings and presents them to Hot Dog, telling him "I think you earned these today" because Hot Dog was still a "nugget" trainee and refused to leave Starbuck by herself when Raiders showed up during a training session.
"Lighten up a little bit. It's only the end of the world."
Played By: Michael Trucco
An athlete on pre-massacre Caprica, the star of the "Pyramid" team Caprica Buccaneers, Anders turned his team into a resistance unit after the fall of the colonies. He was stumbled upon by Kara Thrace and Karl Agathon while the two were trying to get off-planet, and eventually rescued late in Season 2. Becomes a major figure in the resistance on New Caprica, not to mention Starbuck's husband.
Badass: His first appearance is as part of a resistance cell on Caprica. Does a similar thing on New Caprica.
Game of Nerds: Or its in-universe equivalent, Pyramid. In the final episode, Anders — arguably the least cerebral of the Cylons — is revealed in flashback to have a passion for the geometry and mathematics involved in sports.
Real Life Writes the Plot: Trucco suffered a similar spinal injury to Christopher Reeve's in a car crash, resulting in Anders' bullet to the head. He went on to make a near-miraculous full recovery and was able to be an action hero again in "The Plan."
Space ShipBoy: In order to save his life, he gets linked up to a Cylon Basestar.
Louanne 'Kat' Katraine
Played By: Luciana Carro
A "nugget" introduced early in the first season, she soon starts competing with Starbuck for the title of The Ace and even achieves the position of Commander Air Group (previously held by such luminaries as Apollo, Starbuck and Helo) before a Heroic Sacrifice in season 3.
Ascended Extra: Starts out as just another nugget. Grows into CAG before dying.
Special Aide to the President, replacing the deceased Billy Keikaya. Word of God is that Tory was chosen as one of the Final Five precisely because she hadn't yet had much character development. It also created the interesting situation that all three Number Twos in the show are (arguably) Double Agents.
A God Am I: her reaction to finding out her true nature is roughly along these lines, coupled with a dose of "Ascended Fanon?"
Ascended Extra: Started out just as an aide, wound up being one of the Final Five.
Reincarnation Romance: Averted. The [[original Tory and Galen were madly in love, but their Colonial versions are both too distracted by other people and concerns to even notice each other. When they find out, they just snicker. Ultimately averted in the hardest waypossible.]]
Played By: Paul Campbell
Personal aide to Secretary of Education Laura Roslin, he spends one and a half seasons flirting with Dualla before being killed in a stand-off and, eventually, replaced by Tory Foster.
Heroic Sacrifice: Gets shot dead pushing people out of the way of gunfire when a hostage situation turns into a Blast Out. Crosses over into Suicide by Cop, as he was despondent over Dee rejecting him.
Tigh's wife, who miraculously survived the Destruction of the Colonies. She's manipulative, vain and kind of a bitch, a Lady Macbeth with her husband as object-of-control, and Adama notes that she and Saul just tend to make each other worse. During the New Caprica occupation, she seduces a One to free her husband from imprisonment, and then is forced to betray a crucial meeting. In response, Saul poisons her. This makes it even freakier that she turns out to be one of the Final Five.
Introduced as an inmate on the prison ship Astral Queen, Zarek was jailed for acts of terrorism. He sees himself as a Well-Intentioned Extremist working for the common man; whether that's true or not, he's definitely good at politics. After inhabiting the Heel-Face Revolving Door for several seasons, he settles on the bad-guy side, leading a mutiny against Roslin and Adama.
Know When to Fold 'Em: During the search for the Tomb of Athena. His right-hand wants to keep pressing on with their plan to arrange an "accident" for Apollo, but he's smart enough to realise his window of opportunity has closed and abandons that plan. For now.
Averted during his disastrous coup later in the show.
Mythology Gag: Zarek is played by Richard Hatch, who played Apollo in the original series. Zarek spends much of his time antagonizing the present Apollo.
In the first episode, he lectures Apollo on the meaning of his callsign.
OOC Is Serious Business: When President Roslin tells him she is going to give Baltar a fair and public trial, Zarek's initial reaction is to completely freak out and advise that, against all precedent and his own personal convictions, martial law be declared for the duration. Roslin seems genuinely perturbed by just how out of character this is for him.
Principles Zealot: Truly believes that he is working to improve the lot of the common man, and genuinely believes in the principles of freedom and democracy...and is willing to do absolutely, positively anything in pursuit of those beliefs, no matter how underhanded, morally questionable, dishonest, or actively detrimental to the survival of humanity it might be.
An eccentric, self-absorbed and attention-hungry lawyer who takes up the unwanted job of being Gaius Baltar's attorney during his (Baltar's) farcical trial. Trained as a lawyer by Joseph Adama, William Adama's father.
Bunny-Ears Lawyer: Literally a lawyer, and tremendously skilled. The man got Gaius off in what was supposed to be a show trial. He's also very quirky.
Not So Different: Adama points out that he might have made the same decisions as Cain had Roslin, Lee, and the civilians not been there to keep him in check. Also, like Cain, Adama initially wanted to go after the Cylons for revenge.
Psycho Lesbian: According to Blood And Chrome. That her lover was a Cylon is part of her fierce stance.
Sanity Slippage: Her XO notes she's gone through this, becoming more ruthless and cruel.
Smug Snake: She firmly believes she's right and will let anyone know.
The Unfettered: Won't let anything stop her quest, not pesky morals or human lives.
Frst appearing as a Pegasus CIC officer, Hoshi continues to serve in the background throughout the rest of the series, eventually being promoted to Admiral as the ranking officer left with the civilian fleet when Galactica jumps away to fight the show's Final Battle. Was gay for Gaeta.
Ascended Extra: Don't expect to remember his face in the show itself, but in the show's webisodes he was featured as Gaeta's love interest.
Pet the Dog: Saves Helo and Chief Tyrol from a beat down at the hands of some Pegasus crewmembers after the two of them inadvertently end up killing Lieutenant Thorne. He says he does it more for "the sake of the uniform" and that he still does not like them since Thorne apparently saved his life along with at least one other Pegasus crewmember.
Played By: Stephanie Jacobsen
Evil Counterpart: Well, maybe not quite 'evil', but she's a counterpart to Starbuck.
Heroic Sacrifice: Dies in space vacuum repairing the FTL drive to save the ship.
Unexpected Successor: Originaly the chief engineer of the Pegasus, it is suggested that he was one of the only high-ranking officers left.
Played By: Steve Bacic
The result of collaboration between the Centurions and the Final Five, each of these models has many copies, some of which have received more character development than others. The last five humanoid Cylons to be revealed. All turned out to be major players in the human fleet, and the only survivors of a previous Cylon generation pre-dating the Colonies' Centurions.
"Delusional machines! What's the universe gonna come up with next?"
Played By: Dean Stockwell
Initially introduced as a priest from whom Tyrol seeks spiritual guidance, Cavil is revealed (practically on the same day) to be a Cylon. While the Cylons had previously run on a direct democracy, Cavil begins to take over as the series progresses, and his slight personality flaws go center-stage....
Bad Habits: they tend to adopt priestly identities when infiltrating Colonial society.
Being Human Sucks: Or at least that's what Cavil believes. Much of what he does is him lashing out because he believes himself afflicted with human weaknesses. See his Motive Rant below.
Big Bad: Revealed in Season 4 and "The Plan" to be more or less behind everything in the plot since the series began: The Cylon attack on the colonies, the concealment of the Final Five, the lobotomy of the raiders (prompting the Cylon civil war), everything.
Especially the hat-wearing copy on Caprica, which is the only one of his line in the entire series to show mercy and realize that what the Cylons did was wrong. It's a shame that he was likely 'boxed' by the other Cavil, as he's never seen again.
"In all your travels, have you ever seen a star supernova? ... No? Well, I have. I saw a star explode and send out the building blocks of the universe; other stars, other planets, and, eventually, other life. A supernova: creation itself. I was there, I wanted to see it, and be part of the moment. And you know how I perceived one of the most glorious events in the universe? ...With these ridiculous gelatinous orbs in my skull! ... I want to see gamma rays! I want to hear X-rays! And I, I wanna smell dark matter! Do you see the absurdity of what I am?—I can't even express these things properly, because I have to conceptualize complex ideas in this stupid limiting spoken language! But I know I wanna reach out with something other than these prehensile paws, and feel the solar wind of a supernova flowing over me. I'm a machine, and I can know much more. I could experience so much more, but I'm trapped in this absurd body!"
And this is not a motive to sneer at, either. All Cavil wants is what every living thing, everywhere, wants: to be greater tomorrow than it is today. In fact, one could even call it a deeply human motive. Despite this though a great deal of resentment towards his "parents" (his "mother" in particular) colors this. He usurps control of the Cylons, ironically lobotomizes the mechanical ones (who are, in theory, closer to what he wants to be) and even seizes control of Resurrection. Maybe if he could tear himself away from his spiteful efforts to commit genocide against his creators and humanity, he could have worked out a technological means to become what he claimed he wanted to be.
Omnicidal Maniac: Still, it's all in how he chose to express that desire for greatness.
Parental Incest: He knowingly has sex with Ellen Tigh, his "mother" for all intents and purposes (his creator, certainly). Oh, and he apparently resembles her father. Squick indeed. At least she spent their time as an amnesiac...
Straw Hypocrite: Shamelessly exploits the religious fervor of the other Cylons, but is an Atheist himself. His actions become progressively more self-centered and lose even the thin veneer of any idealism as the series progresses.
Younger than They Look: Like all the new humanoid Cylons, he's only 30-40 years old, but was made in the image of Ellen's father. Y'know, being born old might have something to do with why he's so cranky.
Leoben Conoy/Number Two
"I see the universe. I see the patterns. I see the foreshadowing that proceeds every moment, of every day."
Played By: Callum Keith Rennie
One of the first Cylons introduced (in the Pilot miniseries) and one of the first Cylons whom the Fleet finds a copy of in hiding, Leoben has something of a fixation on Starbuck, whom he is sure has a large role to play in the fates of both humans and Cylons. He's right. He goes straight back into creepy territory with his Stalker with a Crush tendencies, though in all fairness he does seem to genuinely love her.
Affably Evil: At first. He genuinely loves and cares for Starbuck in his own twisted way and he can be pretty pleasant company if You can ignore the psychosis.
Super Strength: Is shown snapping cuffs with ease and turning over metal tables with one hand. The otherwise unflappable Starbuck looked ready to jump out of her skin when he showed just how strong he is.
Introduced as a rather pushy reporter doing an exposé on the Fleet (the fate of that copy is never revealed), D'Anna ends up taking center stage by becoming obsessed with discovering the identities of the "Final Five" Cylons, which (according to Cavil) are Things Man Was Not Meant to Know (or Cylons either, for that matter).
Despair Event Horizon: After finding the nuked-out original Earth, she gives up and decides to stay behind and die. And as the Resurrection technology was gone, and that's the last we see of her, that's apparently what happened.
Driven to Suicide: Not suicide so much as letting herself die by being stranded on a barren planet.
Evil Matriarch: Not literally, but Lucy Lawless says she based her performance on this archetype.
Moral Myopia: Even by Cylon standards, she's pretty bad. She constantly preaches about God and condemns humans for Their brutality, conveniently forgetting that Cylons wiped out six billion humans.
Straw Hypocrite: Of the religious variety. She preaches about God and respect for life while ordering mass executions of innocent civilians.
Simon O'Neill/Number Four
Played By: Rick Worthy
Introduced as a doctor running what turns out to be a "Farm"—a giant lab where Cylons experiment with biological reproduction—Simon is polite and well-spoken, the opposite of the Scary Black Man (Cylonism notwithstanding).
"...parents have to die. It's the only way children can come into their own."
Played By: Matthew Bennett
Introduced as a public-relations guy leading a flock of reporters through the halls of the Galactica museum, Doral was described as "Poor Man's Kevin Spacey" by Television Without Pity. He lived up to this name by proving he can totally go Ax-Crazy when he needs to.
Hypocrite: Condemns human suicide bombers, yet one of his defining moments in season 1 has him be a suicide bomber himself.
I Take Offense to That Last One: Insult his intelligence to your heart's content, but don't trash his fashion sense. What makes this difficult is that it's not really that good. In The Plan, Cavil tells the lone Doral still on the fleet that he's too recognizable since they dumped one in Ragnar on suspicion of being a Cylon. The fleet!Doral defensively says that he'd go unrecognized because his (identical style but differently colored) jacket is completely different.
What a Senseless Waste of Human Life: The model who along with a Six tracked Helo on Caprica was prone to some unusually empathetic and insightful thoughts concerning humans, their genocide, love, and the Cylon condition (of inability to love). At one point, he even gets his partner Six to cry while he's not looking by pointing out that Athena is getting to experience human emotion to a degree she (Six) can't even fathom. This in contrast to the model's more commonplace sociopathy and hypocrisy.
Played By: Tricia Helfer
The Femme Fatale Cylon who seduces Baltar, she is later embraced as a hero by her people, and her voice given extra weight in their democracy—even when she suggests that the Cylons attempt peaceful co-existence with humanity. Eventually travels to Galactica along with Athena and Hera, where she spends a lot of time in the brig frakking Saul Tigh, eventually conceiving a (short-lived) child with him. She also joins Baltar in the final battle, and it's implied that the two of them, at least, get a Happily Ever After. Other significant Sixes include Shelly Godfrey, Gina Inviere, Natalie Faust, Lida and Sonja.
The Atoner: Begins to feel regret for her role in killing most of the humans.
Beauty Is Never Tarnished: Usually played straight with Head Six, averted in a number of cases with corporal Sixes such as Gina and Caprica Six in the episode Downloaded
Convenient Miscarriage: Convenient's not the right word, but a pure Cylon baby would have been a game-changer.
Dyeing for Your Art: Tricia Helfer's hair is dark blonde. She initially dyed it for the role, but then turned to wigs when the dye started causing damage. In season four we meet a new Six who has her natural hair.
Mama Bear: She becomes very protective of Hera, even going so far as to snap Boomer's neck after she tried the same on the child.
Ms. Fanservice: A slinky red dress is among the least provocative of her outfits.
Played By: N/A
Basically a plot device introduced late in the series to explain why the numbering on the Significant Seven jumped from Six (given to Helfer) to Eight (chosen by Park). The Daniels were artist-types and much loved by Ellen, which caused a lot of jealousy in the Ones. Eventually, Cavil took efforts to poison the entire Seven line, not only killing all extant Sevens but preventing any others of the type from ever being born.
Introduced as a Raptor pilot on Galactica, the Twist Ending of the pilot/miniseries was that she was a Cylon. Later episodes made it clear that she didn't know she was a Cylon, and that there were programs hidden in her subconscious which caused her to be a Manchurian Agent. This culminated in her putting two rounds through Commander Adama's chest, after which she was offed by a vengeful Cally. Of course, Cylons respawn, and Boomer still had a bigger role to play....
After the producers decided to keep Helo on as a character, their first question was what to do with him. The logical answer would be to pair him up with another Eight, whom he would think was Boomer but was actually a separate instance. This Cylon, who eventually chose the call sign "Athena" (and before then had to be called Caprica-Boomer to differentiate) had a very specific mission: the humanoid Cylons had thus far been unable to conceive biological offspring, and their theory was that The Power of Love was what was missing. Athena's job, then, was to get Helo to fall for her (and then frak her, of course). A High Heel-Face Turn was almost inevitable. She then became the first Cylon character to openly side with the humans.
Mad Oracle: Her words are half gibberish, half prophecy.
Played By: Tricia Helfer
Introduced early in the series, "Head-Six" (as she's known in the writer's room) seemed to be a reincarnation of Caprica-Six (one never shows up when the other is around) that only Baltar could see, and essentially served as Baltar's conscience. She tends to goad him onward into taking actions he would rather not, sometimes even using physical violence to get the job done; she also seems to enjoy seducing him in plain sight.
Not-So-Imaginary Friend: At one time she actually picks Baltar up to face the guard at his cult's quarters, and we (and the rest of the people) see him being lifted by an invisible being.
Spirit Advisor: her main role, beside being an awful tease, is to guide Gaius, give him advice, or simply tell him what to say.
Played By: James Callis
With Tricia Helfer on-set as Head-Six most of the time, it took a while for episodes to come out that focused on Caprica-Six. When they aired, audiences were startled to discover that she had a corresponding Head-Baltar walking around with her. He tends to be more observant as opposed to coercive, often coming up with answers that shouldn't be possible.
Played By: Lily Duong-Walton, Alexandra Thomas, Iliana Gomez-Martinez
The first-ever human-Cylon hybrid. President Roslin orders her death faked and the actual infant assigned to a foster mother, who is killed on New Caprica, causing the child to fall into the hands of the Cylons...
Fake Mixed Race: Is not, in fact, half-Cylon. But in seriousness, the last actress to play her (through various ages she was played by many child actors) was white as the driven snow, while some of the earlier ones were in fact mixed-race.