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As a young girl, Clarice Willow joined the Soldiers of the One in its early days of recruiting on Gemenon. There she quickly became the "brightest star" in the STO training camp. Clarice's faith in the "One True God", however, transcended simple loyalty to the Monotheist Church, becoming what one member of the conclave described as "dyed in the wool" zealotry and Messianic aspirations (CAP: "Pilot", "Unvanquished", "Retribution").
Seemingly at odds with her religious devotion, Willow developed a strong inclination towards alcohol and drugs. As an adult, Willow frequented the Dive Bar in Caprica City where she indulged in opium. Willow was also a heavy drinker at times and particularly enjoyed Scorpian Ambrosia, saying that she was "practically weaned" on it as a child (CAP: "Rebirth", "Gravedancing", "Know Thy Enemy", "The Imperfections of Memory").
Some ten years after her training on Gemenon, Willow immigrated to Caprica where she lived in the capital city, entered into a group marriage, and secured a position of authority within the Athena Academy, focusing on the teachings of the Goddess Athena. At the academy, Willow used her cover as a polytheist cleric to recruit students into the Soliders of the One, bringing several teenagers — the first being Pann — into the Soldiers of the One (CAP: "Pilot", "Rebirth", "Retribution").
In time, Willow became dissatisfied with the Monotheist Church, believing that it had changed in her absence. While it had once held far more radical positions, Willow objected to the Church's softening relationship with the Polytheist Churches around it and the growing distance between the church proper and the STO (CAP: "Unvanquished).
The Resurrection Program
At Athena Academy, Willow mentored Zoe Graystone — daughter of famed scientist Daniel Graystone and computer genius in her own right — who had developed a resurrection program in which life everlasting could be achieved in the virtual world. Convinced that Graystone had been touched by the hand of God, Willow devoted herself to the pursuit of this technology, coming to know it as "apotheosis". Willow believed that apotheosis would bring the Twelve Worlds together under the singular God (CAP: "Pilot", "Gravedancing", "Know Thy Enemy", "End of Line").
As Graystone perfected the avatar technology and created a perfect copy of herself in V-world, Willow gathered support, bringing several members of her group marriage — including two of her husbands, Nestor Willow and Olaf Willow, and one of her wives, Mar-Beth Willow — into the fold. She also enlisted the aid of an informant called Alvo who was embedded deep within the Caprican government's Global Defense Department (CAP: "Pilot", "Gravedancing", "Know Thy Enemy", "End of Line", "False Labor", "Blowback").
The Zoe Avatar
In spite of their close relationship, Willow was left much in the dark about Zoe Graystone's work on the resurrection program. As she neared completion on the project, Graystone made preparations to leave Caprica for Gemenon in secret, but was killed when her boyfriend — Ben Stark — detonated a bomb aboard the MLMT train. Claiming no part in the bombing, Willow was nonetheless left to pick up the pieces, losing access to the Zoe avatar and coming under the suspicion of Agent Jordan Duram of the GDD (CAP: "Pilot").
Unable to locate the Zoe avatar in V-world, Willow reached out to Graystone's best friend, Lacy Rand. Willow attempted to grow closer to Rand, offering to mentor her as she had Zoe in the hopes that Lacy could lead her to the resurrection program. Lacy Rand, however, was already in contact with the Zoe avatar — now trapped within the body of a Graystone Industries U-87 Cylon and deeply distrustful of Willow. Together, Rand and the Zoe avatar concealed the resurrection program from Willow and worked to transport the U-87 to Gemenon as the real Zoe Graystone had hoped to do (CAP: "Pilot", "Rebirth", "The Reins of a Waterfall").
After seeing Daniel Graystone admit on Backtalk with Baxter Sarno that he had spoken to the Zoe avatar, Willow focused on the Graystone Family. Claiming to be returning books that had belonged to Zoe, Willow maneuvered herself into the Graystone home, plied Amanda Graystone with alcohol and gained access to Daniel's private lab. There she used a swipe drive to retrieve information from Graystone's computer. In the process, however, Willow grew close to Amanda, forming a connection to the grieving mother. When Amanda later revealed that she had received visions of her deceased brother Darius, Willow began to believe that Amanda too was touched by God (CAP: "Know Thy Enemy", "The Imperfections of Memory").
As Willow's STO cell focused its resources on apotheosis, another cell lead by Barnabas Greeley pursued a more aggressive course, detonating bombs at two Caprica City Holocafes. Believing the STO cells should be battening down, not calling attention to themselves, Willow became concerned that Greeley's actions would signal weakness within her own cell to the STO authority on Gemenon. Discovering a message sent by Greeley reaching out to other STO cells on Caprica, Willow became convinced Barnabas was attempting to build a power base and struck back. Intercepting an arms delivery intended for Greeley, Willow confronted Barnabas at the Caprica City harbor, pistol whipping him and ordering him to toe the line or face repercussions (CAP: "Gravedancing, "Know Thy Enemy", "The Imperfections of Memory" deleted scene, "End of Line").
Making preparations to fly to Gemenon to meet with the monotheist conclave, Willow sought to solidify her own power on Caprica and kill Barnabas. As she and Nestor Willow drove to the Caprican Spaceport, Clarice was unaware that Greeley had persuaded Lacy Rand to plant a bomb in her trunk. Narrowly escaping the explosion, Clarice and Nestor escaped the explosion unharmed, having left their car on the Pantheon Bridge to rush to the aid of Amanda Graystone as she leaped into the Caprican Bay (CAP: "End of Line").
On Gemenon, Willow introduced her notion of apotheosis to the conclave using a holoband simulation depicting the bombing of Atlas Arena by STO operatives and their subsequent awakening in a "virtual heaven." Skeptical of her proposition and calling it blasphemous, Obal Ferras nevertheless agreed to grant Willow an audience with the Holy Mother. Ferras, however, had other intentions, describing Willow as a zealot to the Holy Mother who sanctioned Willow's "disposal" (CAP: "Unvanquished").
With the Soldiers of the One now marginalized by the Church, Willow reminisced with STO training camp leader Diego about the glory days of the organization. When the time came for Ferras to have Willow's head, Diego was the chosen assassin. Convinced, however, of Willow's connection with God, Diego turned his weapon on Ferras who was then stabbed repeatedly by his fellow conclave members (CAP: "Unvanquished).
Now unopposed, Willow was able to meet with Mother who agreed to provide the necessary resources to complete the apotheosis project. Mother also granted Willow total control over all STO cells on Caprica (CAP: "Unvanquished").
Going into hiding on Caprica after the bombing, Clarice took up residence in a cabin with a recovering Amanda Graystone - still unaware of Willow's involvement in her daughter's murder. Acting quickly to retaliate for the assassination attempt, Willow went after members of Barnabas Greeley's cell who she blamed for the car bombing. Finding them at their respective homes, Willow brutally murdered STO cell members and former Athena Academy students Pann and Hippolyta, further drawing the suspicion of Jordan Duram at the GDD (CAP: "Retribution").
Cornering Greeley in a high rise construction site in Caprica City, Willow handcuffed Barnabas to an explosive, telling him that "others need to learn the price of disobedience." Wilow then detonated the bomb, killing Barnabas Greeley and securing her hold of the STO on Caprica (CAP: "Retribution").
Kidnapping Lacy Rand and locking her in the Willow family home's attic, Clarice had Rand drugged and tortured. With Rand thoroughly demoralized, Willow comforted her and questioned her on the fate of the Zoe avatar. Telling Willow about the destruction of the U-87, Rand admitted that a backup copy of the avatar might exist in a piece of jewelry Zoe Graystone used as a storage device. Satisfied with the information Lacy provided, Willow sent Rand to the Caprican Spaceport where she was put on a ship bound for the STO training camp on Gemenon (CAP: "Things We Lock Away").
The Willow Clan
Becoming more and more suspicious of Willow's activities outside their cabin, Amanda Graystone soon became convinced by Agent Duram that Clarice was involved with Zoe Graystone's death and a secret terrorist leader. Now acting as Duram's confidential informant, Graystone searched the cabin for evidence of Willow's involvement. Finding nothing, Duram instructed Graystone to infiltrate Willow's home (CAP: "Things We Lock Away").
Aware that Amanda could help her retrieve Zoe's pendant which might contain a backup avatar, Willow allowed Graystone to move into her family home. Immediately butting heads with Willow's wife, Mar-Beth, Amanda informed Agent Duram of her difficulties and secured a recording device to plant in Clarice's bedroom. Himself coming under pressure from GDD director Gara Singh to divulge the identity of his informant, Duram provided false information to Singh, indicating Mar-Beth as the CI (CAP: "False Labor", "Blowback").
Singh, who was in fact Willow's informant, Alvo, informed Clarice of the Mar-Beth's alleged deception and provided her with Zoe's pendant. Following the birth of Mar-Beth's child, Willow slashed her wife's throat, dismembering and disposing of the corpse, then reporting Mar-Beth missing to Agent Duram. Analyzing Zoe Graystone's pendant, Willow and two of her husbands, Olaf and Nestor, discovered the backup copy of the resurrection program, began constructing their virtual heaven, and started final preparations for the attack on Atlas Arena (CAP: "Blowback", "The Dirteaters").
Close to the planned date of the Arena bombing, Clarice, Olaf, and Nestor discovered that Clarice's holoband containing the simulation of the attack and other pertinent information had been stolen and replaced with a fake, leading them all to the realization that Mar-Beth had been innocent and that Amanda had been spying on them (CAP: "The Heavens Will Rise"). Clarice led an invasion of the Graystone Estate, following Nestor's recommendation to eliminate the threat to their plan. While holding Amanda and her husband, Daniel Graystone, at gunpoint, Clarice confessed that she had loved Amanda, and went on to argue that she had known Zoe better than Amanda had and that she had been more of a mother to her. Clarice turned angry and announced her intention to execute the two Graystones, but was interrupted when Daniel claimed to want to open himself up to the monotheist faith. Clarice ignored Olaf's plea that it was only a stalling tactic, and she listened intently to Daniel until the formerly dormant U-87 prototype reactivated and violently killed Nestor. With the Cylon hovering over the remaining Willows, Clarice understood that the robot was Zoe. She and Olaf retreated before the robot could strike again (CAP: "Here Be Dragons").
Far away from the Graystone home and trying to regroup, Clarice and Olaf were met in person by Gara Singh, who promised to use the resources of the GDD to deal with the Graystones. After Clarice and Olaf made their own final arrangements, Clarice informed her husband that she would not be with him in the Arena as a suicide bomber: she would welcome the avatars of the other bombers into their V-world heaven, and spread the word of Apotheosis. She ignored his angry response, and claimed that she envied his destiny.
Clarice watched the opening of the game from her home before donning a holoband and entering the heaven program —and coming face to face with the Zoe avatar. Clarice welcomed her warmly and praised her sense of timing before Zoe demanded to know what would happen. Clarice brushed aside Zoe's fears about the deaths taking place in the real world in the name of God. Oblivious to the team of Cylons attached to the Caprican Marines quickly taking out the martyrs before they could detonate their explosives, Clarice welcomed the martyrs' avatars as they appeared in heaven one by one, until Zoe began to challenge Clarice with "blasphemy" and proceeded to tear the heaven program apart. Clarice pleaded with her to stop, to no avail. Clarice finally removed her band. Surrounded by short circuiting and burning computers, she slumped in failure (CAP: "Apotheosis").
The "Differently Sentient"
In subsequent years, Clarice Willow appeared to avoid any serious legal consequences for her crimes and remained free. Seeing the swelling numbers of Cylons in Colonial society and the potential for new followers, Clarice traveled to Gemenon to meet with the Holy Mother, Lacy Rand, for an emotionally tense reunion in which she petitioned for the Church to recognize the "differently sentient." Clarice spent time preaching to congregations of Cylon converts in V-world, speaking of freedom from their human masters and her prediction that they would soon "rise and crush the ones who first gave them life" (CAP: "Apotheosis").