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Working out of a dockside warehouse in Caprica City, Greeley guided his cell in both the planning and carrying out of terror attacks, as well as in prayer groups. Though she never took an active role in his cell, Zoe Graystone was a member of Greeley's circle and had, in some way, made him aware of her "important" project. Active members in Greeley's cell included former students of Clarice Willow, Pann, Hippolyta, Ben Stark, Keon Gatwick and, later, Lacy Rand.
Lacy Rand came to Greeley by way of Keon Gatwick, who believed Greeley was the only member of the Soldiers of the One who could support Lacy's endeavor of delivering Zoe Graystone's" package" to Gemenon. Though it took some convincing, Greeley agreed to help Rand and secured a cargo container that would clear customs. In return, Greeley persuaded Rand to plant a tracking device on Clarice Willow, though, in reality, the device was linked to a sophisticated bomb hidden in Willow's trunk (CAP: "Gravedancing" "Know Thy Enemy", "End of Line").
Conflict with Clarice
Greeley's more active and violent methodology chaffed against that of the more subdued Clarice Willow. Labeling her notion of Apotheosis "some crazy plan that make you into a bouncer in some homemade heaven", Greeley gathered weapons and slowly built a power base, undermining Willow's efforts to lie low. Intercepting a shipment of weapons intended for Barnabas, Willow threatened Greeley at gunpoint, ordering him to toe the line. Greeley did the exact opposite, using the bomb created by Keon Gatwick in an attempt at killing Willow as she traveled to Gemenon (CAP: "End of Line").
Returning from Gemenon with the full support of the Monotheist Church and power over the Caprican STO cells, Willow immediately began murdering the members of Barnabas' cell who had tried to kill her. Trapping Greeley in a highride construction site, Willow handcuffed Barnabas to a bomb and then remotely detonated it (CAP: "Retribution").