01/28/2008 at 09:00 AM EST
's director on the upcoming Batman
sequel The Dark Knight
remembers the late actor as a memorable presence whose charisma on the movie's set was "as invisible and natural as gravity."
"Heath was bursting with creativity," Nolan writes in a tribute that appears in the latest Newsweek
. "It was in his every gesture. He once told me that he liked to wait between jobs until he was creatively hungry. Until he needed it again. He brought that attitude to our set every day. There aren't many actors who can make you feel ashamed of how often you complain about doing the best job in the world. Heath was one of them."
Citing one particular incident, Nolan recalls Ledger "and another actor were shooting a complex scene. We had two days to shoot it, and at the end of the first day, they'd really found something and Heath was worried that he might not have it if we stopped. He wanted to carry on and finish. It's tough to ask the crew to work late when we all know there's plenty of time to finish the next day. But everyone seemed to understand that Heath had something special and that we had to capture it before it disappeared."
The director adds, "Months later, I learned that as Heath left the set that night, he quietly thanked each crew member for working late. Quietly. Not trying to make a point, just grateful for the chance to create that they'd given him."