Jackson Whittemore is a major antagonist/character in the MTV show Teen Wolf. He's Scott McCall's rival, a BHHS student and part of a reptilian monster, the Kanima. He's Lydia Martin and later Ethan Steiner's boyfriend.
He was portrayed by Colton Haynes.
In Season 1, Jackson is the wealthy and arrogant stereotypical student jock as well as Scott's big rival. After the metamorphosis of this one into a werewolf, Jackson becomes jealous of his great capacities in lacrosse and goes to manipulate and blackmail him to obtain this power. He will be bitten by Derek Hale but because of his personality, instead of turning into a werewolf, his body rejects the Bite and he becomes a Kanima.
In Season 2, Jackson continues to suffer the side effects of The Bite and will want to find out why it is happening to him. Without knowing it, he is actually a monster who kills for his "Master" all the people he wants revenge and who is Matt Daehler. Under the latter's orders, Jackson/the Kanima will kill all the people who drowned Matt in his past and will be by his side at the police station to destroy the evidence of his crimes. At the end of the season, he is under the control of Gerard Argent before becoming a werewolf thanks to Derek and his uncle Peter Hale.
Jackson only returns in Season 6, with Ethan being his boyfriend and together returning to Beacon Hills to help Scott and his pack fight off the werewolf hunters. He is as petrified by the Anuk-ite like other allies and eventually returns to London with Ethan.