Actor who had his breakthrough role in October Sky and won a BAFTA Award for Best Supporting Actor for his role in Brokeback Mountain. He also had memorable roles in The Day After Tomorrow, Zodiac, Nightcrawler, and Love and Other Drugs.
He worked as a lifeguard and busboy as a teenager. In 1991, he debuted as Danny Robbins in City Slickers.
He starred in the cult classic film Donnie Darko, for which he won the 2003 Chlotrudis Award for Best Actor.
He is the brother of actress Maggie Gyllenhaal. His parents worked in Hollywood as directors and screenwriters.