One way to look at A History of Violence is as a narratively wonky gangster film pivoting on a tremendous sex scene. And one way to look at David Cronenberg's follow-up, Eastern Promises, is as a narratively wonky gangster film pivoting on a tremendous scene of violence.

Cronenberg doesn't make cheap or unintelligent films. The images stick with you satisfyingly. Eastern Promises--the title sounds like a sequel to Sondheim's Pacific Overtures—boasts a prime atmosphere of aquatic decay. (You watch this London-set film and wonder what Cronenberg could do with present-day New Orleans.)

Cronenberg sets the action on ancient slimy steps leading to a Thames that looks as septic as a Third World river. He gives us the surprise of a baleful, blue cyclopean advertisement for a seafood restaurant dead-ending a street: an enormous octopus three stories high.

"I am dead already," says the Russian gangster protagonist, Nikolai (Viggo Mortensen), as he ritually accepts that tattoos that will mark him as a captain in the Russian mafia. There's life left in him, though, as we see in a brutal fight scene between a nude Nikolai and two leather-clad Turkish killers in the Finsbury Park municipal baths. He may not be dead, but he, like everyone in the film, is submerged in sooty rain and dank basements. The story begins when a junk-addicted, misused 14-year-old checks into an inner-city hospital. She dies, leaving the midwife, Anna (Naomi Watts), to nurse the orphaned baby. Anna finds a diary left behind by the dead girl and becomes an amateur detective, despite the interference of her mother (Sinéad Cusack) and her hard-drinking uncle (Polish New Wave director Jerzy Skolimowski).

A clue surfaces: the book contains a business card for an ostentatious Russian restaurant. There, elderly exiles can come and banquet in the fashion in which they think they remember the old country. That means candied fruits, blood-red borsht and some weird blond epicene shaking his locks at the ancient diners and squeezing the sap out of "Ochi Chyornye" with a banyan.

The manager, Semyon (Armin Mueller-Stahl), is a high-ranking member of the Russian mafia. He's a calm customer, despite the fact that his only son, Kirill (Vincent Cassel), is a degenerate and unreliable weakling. (Kirill by name, krill in this watery world.) The family business includes the sex-slave racket. Trustingly bringing the diary for him to translate, Anna sets herself up for doom. The old man dissembles, gently; he offers to translate and then claims, "I will take what I have done and bring it to your home."

That should be that for the girl. Fortunately, Anna has a defender: Semyon's ironical, tight-lipped, well-dressed and very well informed chauffeur, Nikolai, has an agenda of his own. And he is obviously equipped to deal with any number of Russian wolves.

If Mortensen never seemed like a larger-than-life character before he went to Middle-earth, he is by now the real thing: a great, fearless movie star who can hold down even such an uneasy and melodramatic scenario. Mortensen has Kirk Douglas' end of cinema all to himself today. And in Eastern Promises, he also shows a phantasmagorical side; he's covered with dozens of strange tattoos. The film opens up fresh territory into the rituals of former Soviet organized crime and its tattooed signals.

This criminal language is new even in our thug-clotted cinema. "I am a vor!" (thief) hisses Kirill, demanding respect; he rolls the "r," and the Russian mob suddenly sounds like something out of Star Wars. When these thugs reach the top, they tattoo stars on their kneecaps to prove that they kneel to no one under heaven. Alix Lambert, who studied these prison tats in her documentary The Mark of Cain, served as the resource for the film. Even if one is accustomed to tattoos, these marking are unreadable, genuinely fearful.

But the script ... the script. Steven Knight's script for Dirty Pretty Things also was a case of research underdone by coincidence-plagued impossibilities. Knight is fascinated with a counter-London full of foreigners who rarely tangle with the natives. His scripts play out as modern-day versions of the kind of melodramas that took place at Limehouse or the Wapping Stairs.

Yet he has a brimming heart for the plight of the junkies, sex slaves and overworked illegals. Cronenberg indulges him with literal violins and cellos as the dead girl's diary is read aloud. Knight is sensitive, but he lacks the kind of common sense that made Mona Lisa, in which a different heroic driver busted up a sex-slave ring, a classic.

As in the great film noirs, one doesn't come to Eastern Promises for the plot; one drops in for the atmosphere and the stunning brutality. Those are the only plausible parts of the film—and the sheer authenticity of Mortensen as a Siberian samurai.

EASTERN PROMISES (R; 100 min.), directed by David Cronenberg, written by Steven Knight, photographed by Peter Suschitzky and starring Viggo Mortensen and Naomi Watts, opens Sept. 21.

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