By Emma Jones
BBC News, Cannes Film Festival
Ledger died during the making of the film in 2008
Heath Ledger's last ever movie The Imaginarium of Doctor Parnassus - in which he died during the making of in 2008 - has had its first ever screening at the Cannes Film Festival.
The first shot of the actor is of him hanging from a bridge, seemingly dead. Dramatic in any situation, it's particularly poignant for the audience.
He plays no-good man on the run Tony in Terry Gilliam's fantastical modern morality tale of a travelling actors' troupe which offers their audience personal choices between light and dark and life and death.
The location switches between mundane modern day London and a breath-taking parallel universe that is half Salvador Dali, half Charlie and the Chocolate Factory.
All eyes are naturally on Ledger's performance for the time he remains on screen.
The imaginary world he's created is awe-inspiring, but it's ultimately designed for an art house audience.
It's bittersweet to see him in the flesh and to hear lines spoken to him in the film about those who go before their time: "They are forever young, they won't grow old."
It's also hard to judge his performance as the film cuts between his replacements - Johnny Depp, Jude Law and Colin Farrell.
However, Gilliam's multiple choices work well, with Ledger and Depp actually looking curiously similar.
Lily Cole follows up on her role in St Trinian's with the part of Valentina, Doctor Parnassus's 16-year-old daughter.
But memorable performances come courtesy of singer Tom Waits, who is a beatnik Satan known as Nick, and Verne Troyer - best known as Mini-Me - who plays the tiny Fool to Christopher Plummer's Lear-like Parnassus character.
Gilliam, Lily Cole and Verne Troyer were in Cannes to promote the film
In a movie shifting between reality and the imagination with every scene, he is the only voice actually talking sense.
Gilliam's theme of redemption from rags harks back to his 1991 The Fisher King.
There's no doubt that the imaginary world he's created is awe-inspiring, but it's ultimately designed for an art house audience.
The critics at Cannes loved it, but most cinema-goers would need to see it more than once to start untangling the multiple themes.
As for Ledger, it feels like a post-script performance - he's only in the movie for a third of the time and even if he had lived to complete it, it wouldn't be chalked up as one of his most memorable films.
His many fans, even if they see Parnassus, will probably quietly still attribute The Dark Knight as his last acting role.
That role of the Joker, which gave audiences the full benefit of his range, still remains his fitting tribute.
What others are saying about the film.
The film could have benefited with a lot more hard story and a lot less whimsy. But it is a visually stunning watch. The problem is that it is impossible to unscramble what it all means.
Ultimately, The Imaginarium of Doctor Parnassus is a film with a huge heart and a dazzling eye, but it does little for the very thing it is trying to celebrate: the imagination.
The film's convoluted curlicues are tiring, insisting too loudly on how "imaginative" everything is.
And when it descends into the real world the film can frankly be a bit ho-hum, with some very broad acting from the bit-part crowd players. But this movie, though perfectly amiable, could be for fans only.
This is the purest expression of Gilliam's distinctive sensibility in a long while, complete with outbursts of Pythonesque humour, entrancing dream landscapes, strange creatures, a dapper devil and a wise midget.
To anyone not sympathetic to Gilliam's flights of fantasy, Parnassus will reek of rambling self-indulgence but fans will welcome it as a return to what he does best.
Let the set-pieces commence
Gilliam stays close to his Python roots with images of giant heads and shoes and a musical number that goes 'Join the fuzz - we like violence!'
For the most part Gilliam has toned down the aggressive darkness of his last film, Tideland, pitching at the broader audience he reached for with Baron Munchausen and Brothers Grimm.