Although his parents made their living in showbiz, his director father and screenwriter mother were cautious when a young Gyllenhaal expressed an interest in acting, forbidding him to take a role in 1992's The Mighty Ducks because it required a long location shoot. Still, the budding thespian played a handful of small roles, sometimes in his parents' projects, before making his leading-man debut in the 1999 family drama October Sky. 2001 was his breakthrough year, with standout turns in a pair of indie films: a haunted adolescent in the cult classic Donnie Darko and a gawky teen in love with an older woman in Lovely & Amazing, a performance he more or less repeated the next year opposite Jennifer Aniston in The Good Girl. With his brooding intensity and penchant for offbeat characterizations, he quickly established himself as a first-rate actor. Even his starring role in the bloated 2004 action blockbuster The Day After Tomorrow and high-profile romance with starlet Kirsten Dunst couldn't tarnish his serious image. In 2005 he continued his streak of thoughtful performances and earned his first Oscar nomination as a gay cowboy in Brokeback Mountain.