Of Maori descent and born in Auckland, New Zealand, Bennett's family relocated to Australia soon after his birth. During high school, Bennett played rugby and studied classical ballet and piano before attending the University of New South Wales to study drama.
Previous television credits include starring roles in the successful New Zealand productions Shortland Street, Street Legal, Mataku, Creature Quest, Going Straight, Sinbad and the Minotaur, and Xena: Warrior Princess. His first feature film role was opposite Anthony LaPaglia in the multiple- award-winning Lantana. Other feature film credits include major supporting roles in The Condemned, 30 Days of Night, and The Hobbit trilogy.