Rated PG-13 
Scarlett Johansson doesn’t have a very expressive face. It’s a lovely face, but inert. She purses her lips and every once in a while breaks into a wide, lovely smile, but there are few measures of emotion in between, and her eyes don’t engage—they stay flat, perhaps a little expectant, as though she’s concentrating too hard on her next line rather than what her co-star has to say.

A seemingly expressionless face can be an excellent vehicle for hiding secrets, and that sense of mystery would have made Christopher Nolan’s atmospheric and entertaining “The Prestige” an even better film. But the fact that Johansson neither adds too much nor detracts noticeably from this unique and clever film is a relief to the audience in general, though perhaps a frustration for her fans.

Hers is the ingénue’s role here, anyway. Johansson plays the assistant, Olivia, to the magician Rupert Angier (Hugh Jackman). Set in late Victorian England, an era when illusionists thrilled audiences in packed theaters, “The Prestige” focuses on the very personal rivalry between Angier and his former friend Alfred Borden (Christian Bale). The story is a take on an old cat-and-mouse game, as each tries to top the other in a fierce competition to conjure the greatest trick and become the most prestigious magician working the circuit.

Borden dreams of a spectacular trick first, and the chase is how Angier tries to steal the secret.

The fun here, as is true of most films dealing with magic, is that the story must simultaneously keep things hidden while also showing its hand. When done right, it’s a strange, compelling thing to watch. Magicians, even when dressed up in tuxedos, always seem to bridge the gap between the elegant and the seedy. How do they learn those tricks, and from whom? It’s easy to see why filmmakers are drawn to the magician’s milieu, to the comparison between moviemaking and magic tricks.

In fact, the movie’s title comes from a term applied to the third part of a magic trick: first is “the pledge,” in which the magician entices the audience with a promise; then comes “the turn,” in which the trick is played; and finally there’s “the prestige,” in which the magician returns the thing that appeared lost. That’s the big part of the show—and not at all unlike the structure of storytelling itself.

While Hugh Jackman has yet to find his actorly, break-out part, the role of the suavely elegant Angier suits him about as well as any he’s had so far. There’s always a high quotient of showmanship to his acting, but he does it so effortlessly and good-naturedly that it’s a joy to watch. (This is his second appearance with Johansson this year, following Woody Allen’s “Scoop.”)  Christian Bale is tightly wrapped as Borden—he has a face that flickers between handsomeness and menace (the right combination for “Batman,” of course), and so he nicely captures the working-class background of his character.

“The Prestige” also re-teams Bale with Michael Caine, who played Alfred in Nolan’s “Batman Begins.” Caine here plays Cutter, mentor to both magicians. He’s been in films for about 45 years, and though his hair is thin and gray, his face puffy and lined, he retains that old-fashioned movie star glow. His screen presence is now so warm, it’s hard to remember that he made some of the sharpest, nastiest pictures of the 1960s and early 1970s (see the original “Alfie” or “Get Carter”).

The ambient, echoey script is by director Christopher Nolan and his brother Jonathan, who also shared writing credits on Christopher’s breakout film, “Momento.” “The Prestige” does not travel in reverse order as that film did, but the storytelling is hardly chronological. It may be too determined to dislocate the audience, but once its own internal logic is unlocked, it has a nice, easy rhythm to it.

The film also looks quite beautiful—the London of more than 100 years ago is suitably dank, and the small pubs where the magicians first hone their acts feel as mangy and dirty as you would imagine them to have been. If there’s a complaint, it’s a small one: when Angier travels to Colorado to find the secret to Borden’s trick, there’s snow all around, but the trees are full of leaves. The snow may have seemed like a good idea for the atmospherics, but the filmmakers didn’t quite pull it off.

Setting this story in 1899 makes magic look a lot more fun and sexy than it does today. Perhaps also the filmmakers wish audiences to be more like the audiences were 110 years ago: more susceptible to magic, more naïve, certainly, and I think, probably, on the whole a lot more enthusiastic.

Even so, today’s audiences are lucky to get a film like this. “The Prestige” is like watching an elaborate piece of fin de siecle machinery, one of those huge clockwork toys made of iron that operates on steam and has a thousand moving parts. You’re not quite sure how it works at first, but the mechanics of the thing are fascinating to watch and you keep watching them with determination. You keep watching, of course, until you figure it all out.