Killian Jones, better known as Captain Hook and briefly as the Dark One, is a character on Once Upon a Time, a former major antagonist. He serves as the secondary antagonist turned anti-hero of Season 2 (along with Regina), an anti-hero/protagonist in Seasons 3 and 4, the hidden, true second main antagonist in the first half of Season 5 (while possessed by The Darkness) and an anti-hero/protagonist once again in Season 6. He is portrayed by Colin O'Donoghue. Captain Hook is based on a character from the play Peter Pan.