Zac is a fictional character in the original version of the TV series Battlestar Galactica, portrayed by Rick Springfield.
He is the brother of Captain Apollo and Lieutenant Athena, and the son of Commander Adama and Ila. On his first flight with his brother, Zac is killed by an unexpected Cylon attack preceding what was intended to be peace negotiations.
He subsequently appears in Richard Hatch's relaunch novels set after the end of the TV series, having joined the Seraphs on their Ship of Lights.
Zac's analog in the new Battlestar Galactica is Zak Adama. Zak faces a similar fate in the new series.