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Parr is a Marine stationed on the Galactica.
Parr is among the marines who participate in the mutiny led by Felix Gaeta. After Admiral Adama's drumhead court-martial is adjourned, he is tasked by Tom Zarek to escort Romo Lampkin off Galactica, and possibly execute him. On the way to the hanger deck, he and Lampkin happen upon the aftermath of Lee Adama and Kara Thrace's rescue of the Cylon hostages. While Parr is distracted by Thrace, Lampkin suddenly and repeatedly stabs him with a fountain pen, killing him (TRS: "Blood on the Scales").