Omar Fischer
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Sgt. Fischer is the Sergeant of the Guard aboard Galactica and one of the few Marine NCOs seen in the series.
After "Boomer" Valerii shoots Commander Adama, Sgt. Fischer orders Hollis and Wenzler to remove her from CIC (Scattered).
Fischer is also present when reporter D'anna Biers films a documentary on life aboard Galactica (Final Cut).