He is best known for his starring role as Jack Bauer in the drama series 24, for which he won a Primetime Emmy Award and a Golden Globe Award, and President Tom Kirkman in the ABC political drama series Designated Survivor.

He got his first leading film role in the Canadian drama The Bay Boy. He has since appeared in such films as Stand by Me, The Lost Boys , Young Guns, Flatliners , A Few Good Men , The Three Musketeers , Freeway , A Time to Kill , Dark City , Phone Booth, Melancholia , Pompeii , and The Caine Mutiny Court-Martial.