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Though she was loved by her parents, Zoe was an accident, conceived while the Graystones were busy building their careers. Following her birth, Zoe's mother Amanda Graystone suffered from postpartum depression (CAP: "False Labor").
At the age of six, Zoe was trapped in her bedroom when a devastating fire swept through the Graystones' first home on Caprica. With her father unable to reach her, Zoe survived with the assistance of a vision of herself as an adult. Though she came away from the fire unscathed, Zoe never got over the incident, living with a fear of fire into young adulthood (CAP: "Ghosts in the Machine", "Things We Lock Away").
Zoe later fondly remembered growing up in the Graystones' first home and recalled planting a garden there (CAP: "Know Thy Enemy"). At some point during her childhood, she became an avid reader of Dragon Fighters of Kobol, a fantasy book ((CAP: "Here Be Dragons").
As Zoe grew up, her relationship with her mother was strained. Attributing her daughter's often rude and rebellious nature to the unhappy pregnancy, Amanda Graystone believed that her daughter hated her. She later described Zoe as "angry, defiant, rude, vulgar, obnoxious, unreasonable - just your typical 16 year old girl" (CAP: "Pilot", "Retribution").
Attending high school at Athena Academy in Caprica City, Zoe was extremely proficient in computer programming to the point of being considered a genius. Still, she ran into trouble at school; at least once being caught and disciplined for using her holoband at school. Among her, extracurricular activities were cello and frequent visits to the virtual world where she visited group sex rooms in the "V-Club" (CAP: "Pilot", "Rebirth").
Zoe was schooled in the teachings of the Goddess Athena. Despite her polytheistic upbringing, Zoe came to believe in a singular God, telling her best friend, Lacy Rand, "There is a right and there is a wrong. But only through the One true God can we know the difference." With her boyfriend, Ben Stark, Zoe persuaded Lacy to join a secret monotheist prayer group, though she kept her activities with the Soldiers of the One terror group secret (CAP: "Pilot").
The virtual version of Zoe was created by Zoe Graystone herself using hacked rudimentary emulation software capable of duplicating her own V-World avatar. Graystone programmed the copy - a perfect copy - with roughly 100 terabytes of personal information from other databases. This allowed the avatar to access and translate information from medical scans, DNA profiles, psychological evaluations, school records, emails, video and audio recordings, CAT scans, genetic typing, synaptic records, security cameras, test results, shopping records, talent shows, ballgames, traffic tickets, restaurant bills, phone records, music lists, movie tickets, TV shows and "even prescriptions for birth control" - essentially turning raw data into personality and memory (CAP: "Pilot").
Life's A Good Start
Zoe initially conceived of the avatar program after seeing her father's designs for the U-87 Cyber Combat Unit chassis. Interacting with an illusory version of herself, Zoe realized that she could do more than create a robot body - that she could create life itself. Working from her father's workstation in his home lab, Zoe created the avatar, at first a semi-sentient being, barely aware of its own ability to speak or its own separate identity from the flesh and blood Zoe (CAP: "Things We Lock Away").
Eventually, Zoe brought her discovery to Sister Clarice Willow, headmistress of Athena Academy and closet monotheist, who encouraged Zoe to continue her work - ultimately inspiring Clarice's own notion of apotheosis (CAP: "Unvanquished).
The avatar was soon programmed with a bio-feedback protocol to ostensibly allow it to respond to stimuli in real time as the physical Zoe Graystone experienced it. Despite the achievement, the avatar showed difficulty maintaining resolution, sometimes derezzing back to earlier copies in times of stress (CAP: "Pilot").
Graystone worked with her boyfriend, fellow STO member Ben Stark, to build a private space within the V-Club to house Zoe-A, loosely resembling a monotheist temple on Gemenon (CAP: "Rebirth," "Unvanquished").
Placing the finishing touches on the avatar program, Zoe and Ben prepared to leave for Gemenon; telling Lacy Rand only that there would be a "new family" waiting for them there (CAP: "Pilot", "The Reins of a Waterfall").
As they boarded the MLMT train bound for the Caprican Spaceport, Lacy backed out, leaving Zoe and Ben on their own. Having recently argued with her mother, Zoe used her computer sheet to send a conciliatory message aboard the train. However, that message was never received as Ben Stark detonated a bomb in the name of the "One True God", destroying the Lev and killing everybody aboard (CAP: "Pilot").
Life After Death
In the wake of the bombing and the resulting death of Zoe Graystone, the Zoe-A program continues to run in the virtual world. Upon being discovered by Lacy Rand still functioning within the V-Club, Zoe-A briefly appears covered in blood, fully aware of the bombing and death of Zoe Graystone. Despite initial reservations, Rand comes to treat the holographic version of Zoe as the real thing and introduces her to Zoe's real-world father, wealthy technologist Daniel Graystone (CAP: "Pilot").
At first appalled by the copy of his daughter, Daniel Graystone sees the Zoe avatar as an opportunity to bring his daughter back from the grave. Capturing the avatar's code, Graystone transfers the program to a personal virtual space for analysis. Later transferring the avatar program to the revolutionary Meta-cognitive Processor, a device stolen from the Vergis Corporation of Tauron, Graystone attempts to implant Zoe-A's consciousness into one of Graystone Industries' U-87 battle robots, giving the avatar a physical body in the real world (CAP: "Pilot," "Know Thy Enemy").
At first the experiment seems successful, with the robot taking several steps toward Graystone and speaking a single word - "Daddy" - but the datastream quickly and inexplicably destabilizes, appearing to Graystone as a catastrophic data loss (CAP: "Pilot").
Awakening at Graystone Industries, Zoe-A as the prototype "Cylon" (Cybernetic Lifeform Node) becames the subject of much attention from Doctor Cyrus Xander and lab assistants Philomon and Drew Tanner. Despite the company's attempts at placing duplicate MCP chips into other U-87 robot chassis, the other robots fail to function properly. Unbeknown to the team at Graystone Industries, the Zoe avatar program had bonded to both the original MCP chip and prototype U-87 body, creating a sentient being in the fusion of technologies. Where the U-87s previously failed to prove themselves as capable battle robots, the prototype body containing Zoe-A proves to be an efficient war machine (CAP: "Pilot," "Rebirth," "Unvanquished").
Frustrated by his company's failure to perfect the Cylon technology and faced with a deadline to produce 100,000 combat units for the Caprican Government, Daniel Graystone has the Zoe robot transferred to his home lab for further study. As she is moved back into her old home, Zoe attempts to break free, but is subdued by Philomon and carted in her father's lab where she accidentally injures Drew. Zoe later recalled unease over being touched by the lab assistants: "One guy touched me, and I hurt him" (CAP: "Rebirth").
Back in her old home, Zoe-R is able to reconnect with Lacy Rand. Zoe is also able to access her father's home computer, creating a wireless link to a holoband which allows her to transfer her avatar from her robot body to the virtual world at will. Exploring her father's virtual space with Lacy Rand, Zoe stumbles upon another hacked avatar: that of Tamara Adams, a young girl also killed in the MagLev bombing (CAP: "Rebirth," "The Reins of a Waterfall").
First of a New Race
In her Cylon body, Zoe struggles to maintain some semblance of a normal existence. Savoring the fleeting moments she is allowed by existing in her holographic "skin" in the virtual world (and indulging in simple comforts like virtual food), Zoe's life is dominated by existence as an experimental battle robot. Much of her time is spent being handled by the scientists at Graystone Industries as well as being scrutinized and studied by her father. Upon seeing the Zoe robot in Daniel's home lab, Amanda Graystone unknowingly refers to her daughter as a "monster", believing that Zoe would never have approved of "frakking killer robots" in her home (CAP: "Rebirth," "The Reins of a Waterfall," "Ghosts in the Machine").
Aside from the indignities of life as a robot - including being forced to watch her parents engage in sexual intercourse - Zoe also experiences difficulty controlling her own body. When ordered to perform specific tasks, Zoe is unable to disobey in her robot guise. Presented in front of the Board of Directors at Graystone Industries - and introduced as a new life form to be exploited by the citizens of Caprica - Zoe is forced to rip off her own arm in a demonstration of the Cylons' willingness to comply to human orders (CAP: "The Reins of a Waterfall," "There is Another Sky").
In these experiences, however, Zoe becomes close with Philomon, a Graystone Industries lab assistant tasked with repairing her. Intuitively referring to Zoe in the feminine - despite her generally male appearance - Philomon treats the robot Zoe with reverence, bordering on romantic interest. Setting a test of the U-87's motor functions to music, Philomon allows Zoe to dance - a moment of near normalcy for the adolescent girl (CAP: "Rebirth", "Know Thy Enemy," "Gravedancing").
Escape to Gemenon
With little knowledge of the original Zoe Graystone's ultimate plan for her avatar, the virtual/robotic version of Zoe knows only that she was to be transported to Gemenon where she would help in the effort to spread monotheism to the Tweleve Colonies. Fearing Sister Clarice could not be trusted, Zoe enlists Lacy Rand to join a rival Soldiers of the One cell led by Barnabas Greeley to get her to Gemenon and fulfill original Zoe's plan (CAP: "Gravedancing," "Know Thy Enemy").
As Lacy secures passage for the "package," Zoe seeks to use her connection with Philomon to her advantage. Modifying her avatar to pose as "Rachel," Zoe contacts Philomon through the personals website "V-Match" and arranges to meet him in the V-Club. There Zoe as Rachel initiates a romantic relationship with Philomon, explaining that she used Zoe Graystone's physical parameters to represent her in the virtual world. Over the course of several dates, including a Viper flight simulation, Zoe is able to get Philomon to reveal his work with top secret robotics and attempts to persuade him to release the robot from confinement, telling him to give it "fresh air". However, Zoe unwittingly leads Philomon to a revelation about the problems Graystone Industries had been having with the MCP and U-87 (CAP: "The Imperfections of Memory").
In the real world, Philomon explains his theory to Daniel Graystone who quickly comes to realize that Zoe's avatar is still inside the U-87. Determined to draw his daughter out of the robot, Graystone launches into a series of tests, attempting to elicit a response that will prove Zoe's consciousness is still within the Cylon prototype. Putting the robot through its paces and subjecting Zoe to mind games, Daniel ultimately places a gun in the robot's hand and orders it to shoot Zoe's childhood dog, Caesar. Detecting a slight difference in weight in the weapon, Zoe realizes the gun is loaded with blanks and fires on the dog. Convinced that his daughter would never try to shoot her own pet, Graystone resigns himself to believing that Zoe's avatar is gone for good (CAP: "The Imperfections of Memory," "Ghosts in the Machine").
End of Line
To withstand her father's psychological assault, Zoe vows to become one with the robot body she inhabits, hardening herself against a man and a world she feels betrayed by. Faced with a shortened deadline for the production of battle robots, Daniel orders Philomon to erase the data on the MCP, an act that will delete Zoe's avatar. With little time to escape deletion and permanent death, Zoe urges Lacy to hasten her departure to Gemenon by posing as Rachel, sneaking into Graystone labs, incapacitating Philomon and freeing the U-87. As the deadline approaches and Lacy fails to come through, Zoe reveals herself to Philomon as both "Rachel" and Zoe Graystone in the robot body. Incensed, Philomon triggers a security alert forcing Zoe to attack and kill him. Stealing a Graystone Industries van, Zoe breaks out of the lab and escapes into the outskirts of Caprica City. (CAP: "End of Line")
Following the destruction of the U-87 chassis, the MCP containing Zoe's avatar fails to reboot, allowing Graystone Industries to successfully copy it and begin production of the Defense Department's Cylons. With the robot beyond repair, the U-87 is boxed and sent to Daniel Graystone's home lab. Zoe's avatar, however, lives on, finding herself once again living in the virtual world (CAP: "Unvanquished").
New Cap City
Tracking this Deadwalker to the ruined, New Cap City version of Atlas Arena, Zoe battles Tamara in a brutal, but ultimately pointless fight. Tamara, blames the Zoe avatar for the bombing that killed her real life counterpart as well as her mother, and unleashes angry New Cap City users against her. Enduring a bloody assault, Zoe survives the ordeal - taking solace from the reappearance of the original Zoe's angelic counterpart. Finally, Tamara and Zoe battle one on one, both withstanding horrible injuries. Ultimately, however, Zoe is able to convince Tamara that she is not the original Zoe, nor the bomber, and that together they can fulfill a greater destiny in New Cap City (CAP: "Things We Lock Away).
Acknowledging it as a breeding ground of moral decay and corruption, Zoe and Tamara take it upon themselves to "clean" New Cap City. Appearing nightly at the den of iniquity called "Sinny McNutt's Slash & Cut," Zoe and Tamara engage in combat with its patrons, opening fire on those who are unwilling to leave and derezzing them from the game. The notion of encountering the girls at the bar is a draw to users hoping to either kill them or be killed by them - either way becoming famous. Among the users the Deadwalkers derez are Olaf and Nestor Willow who - despite their work with Clarice Willow on Apotheosis - believe the Zoe avatar is simply an anonymous user "playing dress up" (CAP: "The Dirteaters").
Indeed, the prevailing belief in the real world is that the Zoe avatar is simply a fake and the notion of Zoe and Tamara as "Avenging Angels" spreads into popular culture. As T-shirts spread throughout Caprica City bearing the likenesses of Zoe and Tamara, Daniel Graystone becomes aware of the phenomenon and suspects that it is in fact the real Zoe. Entering V-World and finding the girls at the Slash & Cut bar, Daniel is spotted by Zoe and Tamara who quickly flee (CAP: "The Dirteaters").
Afraid of being captured by Daniel, Tamara suggests they leave New Cap City for other parts of V-World. Zoe, however, rejects this idea, saying that the two had become gods there. Vowing to "forsake these motherfrakkers," Zoe and Tamara use their ability to control code to destroy and reconfigure the urban setting, turning New Cap City into a fortress upon a mountain, surrounded by dense forest - a place to hide (CAP: "The Dirteaters," "Here Be Dragons").
Completing their fortress, Zoe and Tamara's solitude in the new New Cap City is shortlived. Tracking Zoe's avatar through backdoor access to the virutal world, Daniel Graystone is able to locate his daughter and capture Tamara. Holding Tammy in his private virtual space, Graystone attempts to give her a message to relay to Zoe. Zoe, however, enters the private space and attacks her father, stabbing him in the chest and derezzing him. Locked out of the game, Graystone has no other choice but to enter V-World through the "front door", taking his wife, Amanda and Tamara's uncle Sam Adama with him (CAP: "The Heavens Will Rise").
Aware of their entry into the reconfigured New Cap City, Zoe transforms her parent's virtual horses into monsters from her favorite childhood book, Dragonfighters of Kobol, attempting to drive them out of the simulation. Undeterred even after losing Sam Adama, the Graystones push on, finally encountering their daughter in the virtual forest. Rather than trying to force Zoe to go with them, Amanda Graystone tearfully reunites with her daughter and invites her home, telling Zoe that she;s welcome to return to the virtual version of their home any time she wants (CAP: "Here Be Dragons").
Transferring her program back into the U-87 body being repaired in her father's home lab, Zoe discovers her parents held hostage by Clarice Willow and her spouses. Stepping in to defend the Graystones, Zoe uses her detached robotic arm to club Nestor Willow to death before chasing Clarice and Olaf out of the Graystones' home. With the robot incapacitated, Zoe transfers herself into the virtual version of her family home and agrees to work with her father on the creation of a more appropriate robotic body, one with a more humanoid appearance and skin - a "skin job" (CAP: "Here Be Dragons").
Immediately following the break in, STO operative and director of the Global Defense Department Gara Singh uses his authority within the Caprican government to storm the Graystone residence, accusing Daniel and Amanda Graystone of planning the MLMT bombing their daughter allegedly carried out. Alone in the virtual version of the Graystones' house, Zoe is cut off from her parents who are now on the run from the authorities. Viewing CAP News coverage depicting the Graystones as wanted terrorists, Zoe realizes Clarice Willow must be involved and infiltrates Clarice's "Virtual Heaven" as the apotheosis begins (CAP: "Apotheosis").
Seeing STO suicide bombers resurrected within the V-world simulation, Zoe begins to understand her purpose: stop Clarice Willow. Having experienced the debauchery of the V-Club and New Cap City, Zoe argues with Clarice, telling her that a guaranteed virtual afterlife would result in the same kind of moral corruption, this time in the real world. Demonstrating her power to control the virtual world and declaring herself "God," Zoe destroys Clarice's virtual heaven, terminating the avatars of Willow's STO cell, including the avatar of her recently deceased husband, Olaf Willow and forcing Clarice to withdraw to the real world (CAP: "Apotheosis").
The Shape of Things to Come
In the aftermath of the destruction of virtual heaven and the battle at Atlas Arena, Daniel and Amanda Graystone are cleared of the charges leveled against them, devoting their attention and resources to the development of Zoe's "skin job." As Cylons became commonplace in the Twelve Colonies, Daniel Graystone utilizes his expertise in robotics and Amanda her experience in plastic surgery to construct a robotic body, composed of a mechanical skeletal structure with human-looking skin and hair. The body is activated in Daniel's private lab - a perfect, robotic copy of the Graystones' daughter and the true rebirth of Zoe Graystone into the physical world (CAP: "Apotheosis").
Though she no longer inhabits the U-87 chassis, hints of Zoe's avatar remain on the MCP chip which is duplicated and placed into hundreds of thousands of Cylons produced by Graystone Industries. One such Cylon - a U-87s sold on the black market to the STO on Gemenon - remains at the Monotheist retreat with Lacy Rand, having taken part in the overthrow of the church. This U-87 - distinguished by red markings on its chest plating - stays with Lacy as she carries out her duties as the head of the Monotheist Church and the new Holy Mother (CAP: "The Heavens Will Rise," "Here Be Dragons,""Apotheosis").
Delivering a sermon in V-world to a congregation of various Cylon models, Clarice Willow prophesies that a single individual will be instrumental in the inevitable conflict between humanity and the Cylons. Among avatars of U-87s, Cylon servants and Cylon laborers, Zoe-A sits among the congregation and smiles (CAP: "Apotheosis").