Jack Fisk
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Colonel Jack Fisk is the Executive Officer of the battlestar Pegasus (Pegasus).
In a drunken conversation with fellow Galactica XO Saul Tigh, Fisk said that he entered that position following Admiral Helena Cain's execution of the previous XO for insubordination. Fisk later claimed that the shooting was just a joke, although Tigh's instincts told him otherwise as he related the story to Commander Adama.
Fisk's previous position before becoming the XO is not known.