Syfy's Battlestar Galactica took the concept of the original 1978 series and rebooted it into a gritty apocalyptic military drama in 2004. At the center of the changes that made the series work as a backdoor pilot was creating Cylons that blended in as humanoid androids. And as the opening crawl stated, there were many copies. Multiple versions of the same humanoid Cylon could exist at the same time in addition to being reborn should they meet their doom.

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Number Six was an iconic figure of the show, gracing multiple promotional photos in her signature red dress and platinum blonde curls. Between each incarnation of Six, sometimes the differences in personality were minuscule or they diverged greatly. Multiple copies of Six were found throughout the show as pilots, diseased civilians, and assisting Cylons immediately after they had been reborn. But which versions of Number Six stood out in Battlestar’s four-season run and miniseries events?

Armistice Station Six

In the first few minutes of the epic two-part miniseries, Number Six was the first main character introduced to audiences. Although, this particular version of Six was much short-lived in a literal sense. An ambassador, Boxman, arrived at the armistice station, and boldly assumed that he was the only living being on board.

He was shocked by the arrival of the tall Number Six accompanied by two Cylon Centurions. As she kissed Boxman, the ambassador’s eyes widened in horror as Cylons obliterated the armistice station. Thus began the events that led to the attack on the planet Kobol.

Lida

Lida was a smaller presence compared to other Number Six copies throughout the show, and much more innocent-looking with her long white dress and long brown hair. She encountered recently anointed cult leader, Gaius Baltar on the rebel base when he and President Roslin had to escape Galactica during the season four episode “Blood on the Scales.” She became one of the few Sixes to spend the night with Baltar, even though he had plenty of lovers by this point.

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When Lida tried to comfort him after a nightmare, Baltar confessed to her that he felt responsible for the religious following he had cultivated and needed to go back to them.

The Overseer

Dressed head-to-toe in black, the overseer version of Six spent the events of season one ensuring that Karl “Helo” Agathon would develop an attachment to the Number Eight Cylon that looked like Sharon Valerii. The goal was achieved, and the Kobol copy of Sharon became pregnant with a human-Cylon child.

Though she still followed the plan, she distrusted Number Eight due to her human qualities. This copy or another like it confronted resident badass Kara “Starbuck” Thrace in the Delphi Museum, fighting viciously until Starbuck got the upper hand and killed her.

Tough Six

In the event television film Battlestar Galactica: The Plan, this version was not explicitly named but referred to as “Tough Six” in the script. A sex worker usually dressed in leather and metals, Tough Six distracted the marines chasing Shelly Godfrey by donning a wig and a different set of clothing.

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She was also highly aware of the flaws within the plan and made it abundantly clear to Cavil that the Cylons could never win their war because they loved humans too much.

Sonja

After Natalie’s death, Sonja took her place in the Quorum as of "Someone to Watch Over Me." She had the same standard look as the other Number Six copies and could be indistinguishable. But unlike her fellow Sixes’ typical seductress roles, Sonja was a diplomat first and foremost.

Her primary focus was to place Boomer on trial for treason against the Cylons. Once the humans and Cylons landed on Earth in the series finale "Daybreak," she and Adama discussed the future coexistence of Cylons and humans as they planned to repopulate their new home.

Shelley Godfrey

In season one’s “Six Degrees of Separation,” Shelly Godfrey attempted to frame Gaius Baltar as a Cylon collaborator. Though this was technically true, there had been no evidence against him until this point. When Lieutenant Commander Felix Gaeta discovered that her evidence was fake, she disappeared without a trace.

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In Battlestar Galactica: The Plan, it was revealed that Brother Cavil helped her escape by having Tough Six distract the marines searching for her, but he had Shelly killed by shooting her out of an airlock.

Natalie

Introduced in the fourth season episode “Six of One,” Natalie leaned more toward rebelling against the plan, giving Cylon Centurions sentience and starting a coup against Brother Cavil.

She and Admiral Adama formed an alliance based on a quid pro quo deal: if she assisted in destroying the Cylon’s resurrection hub, Adama would release the Final Five into her care after they found Earth. Sharon “Athena” Agathon killed Natalie when the latter came too close to Athena’s Cylon-human daughter, Hera, and Natalie died from her wounds and could not be resurrected.

Gina Inviere

As revealed in the television movie Battlestar Galactica: Razor, Gina worked as an engineer aboard the Pegasus and developed a romance with Admiral Cain, all for the purpose of giving the Cylons the upper hand. After the discovery of her betrayal, Gina suffered severe abuse as a prisoner and she begged for death.

She eventually exacted her revenge against Cain by killing her in season two’s “Resurrection Ship,” but the torture she underwent mentally scarred her. Her trauma complicated her burgeoning relationship with Baltar, who had helped her during her imprisonment and escape from Pegasus.

Messenger Six

Messenger Six, also known as “Head Six” or “Inner Six,” seemed to be a figment of Gaius Baltar’s imagination starting with the miniseries. She appeared without warning and often in fantasy settings such as beautiful houses by the beach or a prophetic vision. Only Baltar could see her for most of the series, but she claimed to be working on behalf of God and gave him instructions to follow in pursuit of God’s will.

By the series’ end, messenger versions of Baltar and Six examined modern-day Earth and discussed the possibility of humankind falling into their cycle of destruction again.

Caprica Six

What distinguished Caprica Six from her other copies was her character growth. Her arc began in the miniseries when she seduced Gaius Baltar and infiltrated the mainframe for the Cylon attack on Kobol. From there, she developed regrets over her actions, wanting to coexist peacefully with the humans on New Caprica but finding no support.

Her romance with Baltar carried across the series, but she additionally found love with D’Anna Biers and Colonel Saul Tigh. After the battle of the Colonies, she and Baltar started a new life together as farmers on Earth.

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