"When I got the call, it was a double tug," Law says of joining the cast of The Imaginarium of Dr. Parnassus. "I liked Heath very much as a man and admired him as an actor. To help finish his final piece of work was a tribute I felt compelled to make."
Ledger was in the midst of filming the role of Tony in the fantasy film, directed by Terry Gilliam, when he died from an accidental overdose of prescription drugs in his New York apartment on Jan. 22, 2008, at age 28.
Determined to finish the movie, Gilliam kept Ledger's work intact, and hired Law, Johnny Depp and Colin Farrell to round out the role of Tony – each playing a different incarnation of the character after he steps through a magical mirror.
"To help Terry finish his film was an honor paid to a man I adore," Law says. "Though we were all there in remembrance, Heath's heart pushed us with great lightness to the finish."
Lily Cole, who plays the female lead as Tony's love interest Valentina, says it was a struggle to resume filming just a month after Ledger's death.
"We'd had a month to absorb that situation, which by no means is enough time to get over it, but it was a month to think about finishing the film," Cole tells Film Review Online.
The Imaginarium of Dr. Parnassus, which Gilliam has dedicated to Ledger, opens in limited release in the U.S. on Christmas Day and in wide release on Jan. 8.