Everyone knows a magician never reveals his secrets. So you may never figure out the "how" -- and it's often not that important to figure out the "why." Why does he do the tricks he does? Why does he want to captivate the audience? For many magic acts, the answer is simply "to dazzle them."

But for Eisenheim, a magician who seems to appear out of nowhere in turn-of-the-century Vienna, the answer to "Why?" is at the crux of The Illusionist.

Based on the short story "Eisenheim the Illusionist" by Steven Millhouser, Neil Burger's 2006 film is the dangerous, seductive story of a dangerous, seductive time.

Much of the seduction comes from Edward Norton as the mysterious illusionist. Born to humble station in Vienna, he is threatened and booted out when his childhood friendship with the wealthy Sophie (Jessica Biel) becomes too close. Eisenheim drops out of view for years, reappearing as an adult after wandering the world. He soon is the toast of Vienna, conjuring spirits from the afterlife, melding his illusions with philosophical discussions on time, death and power.

And it's the subject of power -- who deserves it, who has it, all the ways it can be abused, whether the ends justify the means -- that intrigues The Illusionist.

Because Sophie, now all grown up, isn't just the favorite of some wealthy Viennese man; she's the soon-to-be-betrothed of Crown Prince Leopold (the beautifully glowering Rufus Sewell). Leopold may be forward-thinking compared to 19th-century leaders, but he's as ruthless in love and politics as any old ruler was. He doesn't like the adulation Eisenheim is getting from common Viennese, he doesn't like the attention Eisenheim gets from the upper crust and he definitely doesn't like the obvious attraction Eisenheim shares with Sophie.

Caught between the Crown Prince he serves and the illusionist whose intelligence he admires is police Inspector Uhl (Paul Giamatti, finally given the chance to be smooth, not just the bumbling sidekick). It's a cat-and-mouse game between the three men, complicated even further when Sophie turns up drowned in a river. Eisenheim publically charges Leopold with murder; Leopold orders Uhl to put an end to Eisenheim.

The Illusionist pulls a bit from history for its characters of Leopold and Eisenheim (who astonishes his audience with an illusion harking back to "The Blooming Rose Bush," performed by a rough contemporary in real life, Karl Germain), and for the flavor of early-20th-century Vienna.

Even if you happen to figure out the "how" and the "why," The Illusionist is still a ravishing look at the fine line between innocence and murder, between just and unjust punishment.