Nicholas Brody

Nicholas Brody is the deutragonist of the first three seasons of the Emmy award-winning tv show Homeland. While he was an anti-villain in the Season 1 and the first half of Season 2, he later becomes an anti-hero from there on.
He is a Sergeant in the US Marine Core who in 2003 was captured and imprisoned by Al-Qaeda for 8 years before bering set free and returned home by US military and is given a warm welcome at home by the American people. However, CIA-agent Carrie Mathison rightfully suspects he was turned to Al-Qaeda during his captivity and was in fact sent home to carry out an attack. In spite of that, Brody eventually redeems himself and instead helps out the CIA in stopping another attack planned out by Al-Qaeda's leader Abu Nazir.
He was portrayed by Damian Lewis.