Film Your Mileage May Vary
SPOILERS AHOY.
The Illusionist tries to mesh two genres—a lush romantic melodrama set in a fairytale land of duchesses, princes, and intrigue (a la The Prisoner of Zenda) with the moody mystery of a policeman trying to unravel the secrets of a magician who's been mixed up in murder (like The Prestige). And it nearly works, but not quite. In the end, the mystery's final twist destroys the melodrama.
I badly wanted the movie to work. Who doesn't love that Edwardian fantasy land filled with delectable dukes and pristine princesses, political intrigue and despairing love? It is Ruritania, Austria, or somewhere in Eastern Europe where anyone worth their salt is an Archduke or a Princess von something, and titled dignitaries mix with gipsies, international adventurers, and even illusionists; a not-quite civilised place where men still fight duels for love and honour.
The Illusionist pretends to be this kind of story. But it soon gives away its true nature. When Eisenheim and Sophie fall into bed, there's no pretence left to be kept up. It isn't set in 1900s Ruritania—it's firmly planted in the 2000s, where "whore" is just a mean-spirited, nasty epithet and not an insult to be washed out in blood (if false); where a woman in love has no regard for her reputation or honour, and where the only thing on anyone's mind—and the only indication of morality—is social class.
As the end of the film drew closer, I thought it could redeem itself. The policeman gives up conspiring with a traitor. The murderer kills himself. The Emperor restores justice. The illusionist, having given his beloved justice, retires as mysteriously as he came.
It would have been a perfectly satisfying ending. Just make the policeman's moral quandary a touch more wrenching, and presto—the movie is about whether he will do what he knows to be right. But no—they had to have a shocking twist. And it is revealed that the lady was alive all along, and she and the illusionist framed an innocent (if repulsive) man for her murder and caused his suicide.
This unravels the plot of the melodrama—it cannot survive the revelation that the villain isn't the murderer—the hero is. The moral of the story ends up being that if you are a Crown Prince and beat women, you are evil, but a commoner who frames an innocent man is OK. There's proletariat morality for ya.
Film How Not To Do Magic vs Mundane
The Illusionist already has a lot I dislike about it. I dislike the clichéd costume drama device of class disparity = conflict. I dislike how Norton's idea of "mysterious and brooding" means squinting and smirking a lot (leave those affectations to Derren Brown). The Illusionist's greatest failing, however, is its total lack of tension.
With a "maybe magic, maybe mundane" story, it is necessary to keep the mystical events ambiguous enough to be explained either by magic or by tricks. This is vital if you want to make it a recurring theme to your story. The Illusionist fails to do this. The illusions are so complex, they can't be explained by anything other than magic. Even though the movie tries to suggest that there are mechanics and trickery involved, these (WWI era) props would have to be so implausibly sophisticated, they might as well be magical. Cursory research tells me that many of the tricks in the film are based on real tricks performed by 19th Century magicians. Perhaps if the film actually recreated those tricks properly, instead of using CGI versions, the audience might have seen how the tricks could be done without magic.
Once it becomes apparent that the illusionist can basically do anything with his magic/impossible props, all the tension evaporates. There is no way the Prince can threaten such an overpowered hero. The magic is so flaky and vague, the writers could Ass Pull any solution to a problem. Because of this, there is no conflict. There is no mystery. There is no point in feeling concerned for the heroes, because they will inevitably sort themselves out. Unless you have an attraction to smug looking men, I wouldn't bother with this film.