There's no law that an action movie has to make sense — it can just be all action. "Salt" is a demonstration of this. However, the best action movies consist of more than nonstop frenzy, and they can sell their wildest implausibilities — James Bond with his jet packs and underwater tuxedos, Jason Bourne still alive in the sea after taking two bullets in the back — with a spirited blend of style, pace and personality. In its indifference to such elements, "Salt" is a demonstration of how important they are.

The story does kick off with a clever hook. Top CIA agent Evelyn Salt (Angelina Jolie) is in the middle of grilling a Russian intelligence operator named Orlov (Daniel Olbrychski) when he tells her that the Agency has been infiltrated by a Russian mole, whose ambitious mission it is to destroy the United States. Salt asks Orlov the mole's name. "Salt," he says.

Two of Salt's fellow agents have been watching this interrogation, and they're naturally startled. One of them, Ted Winter (Liev Schreiber), says he's certain that Evelyn can't be a mole. The other, however, a hardass named Peabody (Chiwetel Ejiofor), isn't so sure. Salt herself doesn't stick around to explain — she takes off. All kinds of pursuers leap into action, and as the chase proceeds, we marvel at her ability to dispatch hordes of heavily armed soldiers (all terrible shots) and her easy access to guns, chemicals and high-end designer clothing. (At one point in her flight, attired in a flowing fur-trimmed cape and matching hat, she looks like a fugitive from a fashion shoot.) She has also brought along a venomous pet spider. Well, her husband's pet spider. Her husband's name is Mike (August Diehl), and he's an arachnologist so esteemed, we're told, that he has "unlimited access to the border areas of North Korea." This would explain why he was on hand when Salt was freed from the North Korean prison where we'd seen her being beaten to a pulp in her underwear at the beginning of the movie. Unfortunately, it doesn't explain what the Norks have to do with the story, which seems to be nothing.

When it's not swamped in uproar — one damn thing after another — the movie attempts to maintain its focus on the Russian mole. Or moles, actually — because there's a whole nest of them, raised from childhood to become deep-cover saboteurs. (We see the devious nippers being schooled in the nuances of colloquial English by watching old "Brady Bunch" episodes!) At first we don't think Salt is one of these spies, but then it begins to seem that maybe she is. Anyone hoping for a resolution to this question should be aware that the movie is openly intended to be the first installment of a franchise. Stay tuned, presumably.

The picture is light on CGI and heavy on stunt work, a lot of it impressive. In one sequence, which must have been tricky to stage, Salt drops from a bridge onto the top of a speeding truck down below, then leaps onto the top of another truck, then onto a third, and then, down on the street, yanks a passing motorcyclist off his chopper and tears away on it. There's also a heavy-damage freeway chase that ends with Salt driving a car off an overpass and landing with a crash on a tangle of taxis (and then, of course, walking away). The Bourne movies also traffic in this sort of fantastical mayhem; but in those films, the action has a rush to it — it sucks us in. Here, Phillip Noyce, who directed the Jack Ryan CIA thrillers back in the early '90s, never quite closes the audience-action gap — we don't feel like participants, only observers.

The picture also makes puzzlingly little use of Angelina Jolie's skill as an actor — she's been directed to remain, for the most part, stone-faced and closed-off throughout. (Kurt Wimmer's script is no help: It seems to have been converted from the Tom Cruise vehicle it was originally intended to be with little more than a change in pronouns.) Jolie could have brought humor and emotion to this character; but the complex depths Salt is purported to have remain pretty much as inscrutable at the end of the film as they were at the beginning. Will all be made clear in the sequel (indicated by a rather Bourne-like conclusion)? We'll have to wait and see. Judging by this somewhat leaden opening installment, though, it may be a longer wait than the filmmakers had planned.

Check out everything we've got on "Salt."

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