Jake Gyllenhaal filmography character, a "sullen" and "schizophrenic" teenager, made him a cult hero. Although the film was critically acclaimed, it failed commercially. Gyllenhaal starred in the 2004 disaster film "The Day After Tomorrow", which, despite receiving mixed reviews from critics, was a commercial success at the box office. In 2005, he co-starred as Jack Twist opposite Heath Ledger in the romance drama "Brokeback Mountain". The actors portrayed two men that fall in love during a sheepherding expedition. The roles earned both Gyllenhaal and Ledger critical acclaim and Academy Award nominations. That same year, he starred in the drama films "Jarhead" and "Proof".
Heath Ledger had in any way led to his death (as Denby and others suggest), Ledger's co-star and friend Christian Bale, who played opposite him as Batman, has stressed that, as an actor, Ledger greatly enjoyed meeting the challenges of creating that role, an experience that Ledger himself described as "the most fun I've ever had, or probably ever will have, playing a character." Terry Gilliam also refuted the claims that playing the Joker made him crazy, calling it "absolute nonsense" and going on to say, "Heath was so solid. His feet were on the ground and he was the least neurotic