EASTERN PROMISES. How did a director known for gut-busting horror become one of our great handlers of actors? In the beginning, when Cronenberg was transforming humanity for fun and profit, he didn't need much acting. But when he ascended into big-time filmmaking, Cronenberg inverted the perspective, focusing on human resistance to monstrosity. This had the rare effect of making his work both more marketable and more mature. In The Fly, even before his lab misfortune, Jeff Goldblum's Seth Brundle seemed eager to slip the surly bonds of mere humanity, and the film might have been another sly comedy of the New Flesh, but Cronenberg let love complicate his story, and the adventure became an agony, and even something close to a tragedy.

Lately Cronenberg has been escalating the moral stakes of his stories, and putting a greater burdern on his actors. He's been lucky with his actors, for the most part. In Eastern Promises, Cronenberg brings back Viggo Mortensen, the moral border-crosser of A History of Violence, as the tranformational hero. He is the Russian mobster who translates between the "good people" of London, portrayed by Naomi Watts and her part-Russian family, and the monsters of his mob, bossed by Armin Mueller-Stahl, whose depravity is indicated by his incapacity to express any feelings beyond contempt and anger. Mueller-Stahl's son, played by Vincent Cassell, has inherited the anger, but no talent for contempt -- petulance and insolence are the best he can manage. Mortensen has the contempt at existential levels, which may be why the boss virtually substitutes him for his real son -- a dangerous move for all concerned, as it happens.

The mob dynamics are fascinating, which may be why Cronenberg shows a lot of them, even though the action is supposed to be in the interplay between Mortensen's crew and the normals. The McGuffin is a baby left behind by a dying mob slave. The Londoners wish to save and redeem the baby; the mob boss wants whatever will best protect him, which may require its death.

That "may" is part of the problem. There is some dramatic merit, especially in the beginning, in keeping the necessity of the baby's death an open question. For one thing, it allows Mortensen's character and Watts' to interact on something other than strictly adversarial terms. Unfortunately, while Mortensen is superb, showing both the scars on his soul and the soft spots still remaining, Watts is just terrible. Her only identifiable character traits are those that have been announced by the other actors. (Are she and her BFF Nicole Kidman part of some bad actress sorority? Do they practice bugging their eyes and smiling slyly together?) This underrealized attraction leads to a silly motorcycle baby-chasing climax, which is even more ridiculous than it sounds.

I think Cronenberg saw in this story a way to further explore the moral divide examined in A History of Violence. But with a mob as thoroughly (though entertainingly) black and damned as this one, a heroine who is only pretty and well-intentioned, and a man standing between whose whole life is invested in not showing his true feelings, you don't have a moral divide, you have a moral silhouette. This may be why so much energy goes into the set-pieces, including the brilliantly choreographed bathhouse fight scene. They're fun to watch, but in the end they're just bloody filigrees. It may be that, in giving his actors more to do, Cronenberg has fallen into the trap of letting them do too much of what should be his job: inventing a reality that offers more resonance than scene-study exercises.