When Jake Gyllenhaal's Brokeback Mountain co-star Heath Ledger died unexpectedly in 2008, Gyllenhaal says it had a huge emotional impact on him.
In an interview with People and Entertainment Weekly, Gyllenhaal said, "Personally, it affected me in ways I can't necessarily put in words or even would want to talk about publicly."
"In terms of professionally," he said, "I think I was at an age where mortality was not always clear to me." Gyllenhaal noted that it helped him understand that fame was fleeting: "None of the attention or synthesized love that comes from the success of a film really matters at all. What matters is the relationships you make when you make a film, and the people you learn from when you're preparing for a film. That changed a lot for me."