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His view on the Cylon Prototype clashed with Philomon's, particularly when it came to Philomon's feminization and personification of the robot. Tanner's treatment of the robot — and, unknowingly, of Zoe-R — resulted in his finger tip being severed after attempting to repair the prototype (CAP: "Rebirth"). He eventually recovered and returned to work on the project (CAP: "End of Line").
Several months later, Tanner was approached by Graystone Industries CEO Daniel Graystone and Graystone's wife for his help. Tanner was highly suspicious at first, as the two had been publicly accused of terrorism and were fugitives from the law. However, he was convinced by Graystone's promise to pay back both his friends and his enemies accordingly once the accusations were lifted. Tanner accessed a high security Graystone Industries laboratory, and retrieved a specialized laptop computer that Graystone eventually used to summon more than two dozen U-87s in an attempt to stop the suicide bombing of Atlas Arena (CAP: "Apotheosis").