James Lyman
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A member of Deck Crew 5 under Chief Tyrol, often seen working alongside other crewmemembers Socinus and Cally in the hangar bay.
When President Roslin made it public knowledge that Cylons are now capable of mimicing human form, paranoia spread throughout the Colonial Fleet. Cally and Socinus argued with Jammer that everyone shouldn't become suspicious and stop trusting one another or the Cylons got what they wanted. Jammer told them that the time for that kind of thinking was in the past and it was "every man for himself now" (Litmus).
When Cylon Centurions boarded the Galactica {Valley of Darkness), Apollo and a team of Marines found Jammer hiding unharmed in a small arms locker room filled with crewmen the Cylons had killed.