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Gage is happy to finally see some alcohol from the still created by the deck hands on Galactica.
Much to Chief Galen Tyrol's and Karl "Helo" Agathon's discomfort, Gage and a handful of other Pegasus crewmembers describe the gang rapes by Pegasus crew of a captured copy of Number Six that called herself Gina Inviere. These rapes were apparently led and tacitly encouraged by the battlestar's "Cylon interrogator", Lieutanant Alastair Thorne.
In retaliation for Thorne's death, Specialists Vireem and Gage (with the help of two Marines) bind and begin beating the incarcerated Agathon and Tyrol in Pegasus brig until Colonel Jack Fisk catches them in the act and dresses them down (TRS: "Resurrection Ship, Part II").
After the destruction of Pegasus, Gage joins the crew of Galactica.
Later, after the discovery of the devastated Earth, he joins Felix Gaeta's mutiny against Admiral William Adama. Gage and some other mutineers raided the Agathons's quarters, kidnapping the two officers and their daughter, the human-Cylon hybrid child Hera. Gage antagonized Karl Agathon, saying that Thorne's death and Agathon's subsequent promotion were unjust, and had Agathon beaten into unconsciousness. He also threatened to rape Sharon and made a second threat to her safety when he dropped her off in the brig. Specialist Gage then took over Gaeta's position in CIC when Gaeta took on the role of Galactica's commanding officer (TRS: "The Oath").
Gage never gets the chance to follow through with his threat. Mere hours after the rebellion begins, Adama and his supporters storm the CIC. The mutineers surrender without a fight and Gage is taken away along with the rest of the mutineers (TRS: "Blood on the Scales").
Specialist Gage is presumably incarcerated on Astral Queen for his actions in the mutiny.