Ledger's last performance hits screen in Cannes
The film maker's first thought when Ledger died in New York was to ditch "The Imaginarium of Doctor Parnassus," which was only half finished.
But encouraged by people around him to continue, and helped by actors Johnny Depp, Jude Law and Colin Farrell who played Ledger's character in three separate dream sequences, Gilliam eventually completed the movie.
"The choice I made was to close the film down," Gilliam told reporters at the Cannes film festival, where the out-of-competition movie has its world premiere.
"I couldn't see how we could finish it without Heath because we were in the middle of production.
"Fortunately, I was surrounded by really good people who insisted that I shouldn't be such a lazy bastard and I'd better go out and find a way of finishing the film for Heath.
"That's what we did."
Gilliam decided to use three actors rather than one to complete the role of Tony, made possible because they appear in a land of the imagination entered through a magic mirror.
"I started calling friends -- Johnny Depp, and he said 'I'm there'. And I basically was just calling people who knew and loved Heath.
"Everyone in the cast and everyone in the crew was determined that this film would be finished and everybody worked longer, harder and somehow we got through. It was really ... people's love for Heath that propelled this thing forward."
ENERGY AND AD-LIBBING
Gilliam praised Ledger, who won a posthumous Oscar for his performance as the Joker in Batman blockbuster "The Dark Knight," for his enthusiasm and energy on set.
"Heath was enjoying himself so much and he was ad libbing a lot which I don't really allow that much ... in my films. He got everybody else going. Everybody was just energized by Heath, he was extraordinary, he was almost exhausting."
Ledger plays Tony, who is found hanging from a bridge in London but is revived by Anton and Valentina, members of a horse-drawn traveling theater which has the power to allow people to walk into a world of their dreams.
Christopher Plummer stars as Doctor Parnassus, an man who has lived for centuries after making a pact with the devil, performed by Tom Waits.
The devil plans to take away his daughter Valentina when she turns 16, but gives Parnassus one last chance to save her.
The action moves from the streets of London and inside the rickety old wagon to fantastical, special effects-laden landscapes that represent people's imaginations.
"I just know that story telling and the restructuring of the world through stories is vital," Gilliam said. "What I'm talking about is using one's imagination to expand the possibilities and the view of the world people have."
Ledger's family, who Gilliam said supported him completing the film, have yet to see it.
"What was important for me was just to make a film with Heath's last performance up there alive and well, and I think they're going to be delighted by it."
(Editing by Jon Hemming)
