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Venner is in charge of guarding Roslin while she is imprisoned in the brig after Commmander Adama terminates her presidency and arrests her. Venner asks that she pray with him during a Cylon attack. He carries a set of white prayer beads (TRS: "Scattered").
Soon after, Galactica is boarded by Cylon Centurions, and Lee Adama orders Venner to lead Roslin to sickbay and to safety. While making their way through the ship, they are nearly killed in a run in with the Centurions (TRS: "Valley of Darkness").
Venner is recruited by Keikeya in the plot to free Roslin. He participates in her escape from Galactica by pretending to be the victim of an assault that frees Roslin from the brig (TRS: "Resistance").
He apparently survived New Caprica and, although unseen, is with Roslin when she threatens to have Baltar thrown out an airlock after his return from the Cylons (TRS: "Taking a Break From All Your Worries").