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The resurrection program was a project undertaken by Zoe Graystone and later her father, Daniel Graystone, as a way to continue life after death in the Virtual World. It was the basis of Sister Clarice Willow's notion of apotheosis.
In the years prior to the First Cylon War, Zoe Graystone - a brilliant programmer - conceived of creating life in the form of a holographic avatar after seeing her father, Daniel Graystone'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, imbuing it with her own memories but also a separate identity from the flesh and blood Graystone (CAP: "Things We Lock Away").
What resulted was a "perfect copy," programmed with roughly 100 terabytes of personal information from online databases and personal journals. The avatar's personality was comprised of 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 an identical copy of Zoe Graystone (CAP: "Pilot," "False Labor").
The avatar was also programmed with a bio-feedback protocol that ostensibly allowed it to respond to stimuli in the real world as the physical Zoe Graystone experienced it. Despite the achievement, the avatar showed difficulty maintaining resolution, sometimes "de-resing" back to earlier copies in times of stress or over-stimulation. Following the sudden death of Zoe Graystone in the Caprica City MagLev bombing, however, the avatar showed itself to be a fully realized extension of Graytone, though restricted to the Virtual World (CAP: "Pilot").
Stricken by the loss of his daughter and shocked by the discovery of the living avatar, Daniel Graystone sought to bring Zoe back to life, by implanting the avatar into the body of a robot. Utilizing the preexisting U-87 chassis and a meta-cognitive processor stolen from the Vergis Corporation of Tauron, Graystone began the process of transferring the avatar, when its datastream was disrupted and the program was seemingly lost (CAP: "Pilot").
As Zoe Graystone perfected her resurrection program, a movement parallel to the technical achievement was occurring in the spiritual world. Inspired by Graystone's achievement Zoe's mentor, Sister Clarice Willow, saw the potential for life after death in the Virtual World as a religious opportunity. Dissatisfied with the monotheist movement as it stood and the actions of the Monad Church, Willow believed the program would serve as a lightning rod that would unite the Twelve Worlds under the "One True God." Willow called this "Apotheosis" and rallied many of the Soldiers of the One of Caprica in its pursuit (CAP: Pilot, "The Reins of a Waterfall," "Know Thy Enemy," "End of Line," "Unvanquished," "Retribution," "False Labor").
Encountering resistance to the notion of Apotheosis from many among the STO on Caprica - including rival cell leader Barnabas Greeley - Willow presented her idea to the monotheist conclave on Gemenon. There she produced a holoband simulation that depicted the bombing of Atlas Arena in Caprica City by members of the STO and their subsequent rebirth in a virtual heaven. Projecting the casualties of such an act in the tens of thousands, Willow described only a chosen few - those who had rejected the prevailing polytheist beliefs - living on. In an age, Willow said, in which myth and mystery had been replaced by science, the monotheist church would be the only religious movement capable of providing a tangible and assured afterlife (CAP: "Unvanquished").
Still finding those who objected to the very notion - conclave member Obal Ferras describing it as blasphemous and "tacky" - Willow sought the wisdom of church leader Mother. After arranging the murder of Ferras, Willow was persuasive and able to secure power over all STO on Caprica. What followed was a violent consolidation of power as Willow asserted control over all the cells on Caprica, eliminating dissenters like Greeley and kidnapping and torturing Zoe Graystone's best friend, Lacy Rand in an effort to recreate Graystone's resurrection program (CAP: "Unvanquished," "Retribution," "Things We Lock Away").
Seeing it as a potential for profit for his struggling technologies company, Graystone Industries, Daniel Graystone also sought to recreate Zoe's resurrection program. Struggling to duplicate his daughter's avatar program, Graystone admitted to feeling like a hack, creating a virtual version of his estranged wife, Amanda Graystone. Unlike Zoe's avatar, however, the Amanda avatar was unable to surpass the base programming of all holograms, heavily emphasizing sexuality and the desire to please while simply parroting information like journal entries as memories (CAP: "False Labor").
Under heavy pressure from the Ha'la'tha crime syndicate that owned a large percentage of Graystone Industries, Cyrus Xander created a commercial for the resurrection program and hoped to market the product under the name "Grace" (CAP: "False Labor").