"I am driver," explains Viggo Mortensen early in David Cronenberg's Eastern Promises. "I go left. I go right. I go straight ahead. That's it." In fact, moviegoers should be pleased to know that the moral maneuvers undertaken by Mortensen's character, a low-level hood in London's Russian underworld, are considerably more interesting than advertised: swerves, veers, dips, even a u-turn or two. In structural terms, the protagonist of the film is a midwife played by Naomi Watts. But on a gut level this is Mortensen's movie, and he makes the most of it.
The film begins elementally enough with one birth and two deaths: A teenage prostitute gives birth to a daughter, but bleeds to death during delivery; a Russian mobster, meanwhile, has his throat brutally slit--"sawed" would be a more accurate term--as he sits in a barber chair. The events prove to be connected when Anna (Watts), the midwife overseeing the tragic birth, finds among the mother's possessions a diary in Russian and a business card for the "Trans-Siberian Restaurant."
Visiting the restaurant in hope of finding someone who might have known the girl, she meets the owner, Semyon (Armin Mueller-Stahl), a pleasant, fatherly chap who is also, as it happens, the murderous overlord of the local Russian Mafia. He takes an interest in the diary and offers to translate it. When he does so, he finds more than a few unfortunate, perhaps actionable, revelations in it concerning himself and his weak-but-vicious son Kirill (Vincent Cassell). By now, however, Anna's Russian uncle has also read the diary and told her of its ugly contents--and Semyon is aware that she's aware of them.
It's remarkable how extraneous Mortensen's character, Nikolai, is to the early proceedings, because from the beginning he looms over the film. A glorified errand boy and paid friend and chaperone for the childish Kirill, he is omnipresent, quietly smoothing over rough patches and cleaning up messes. He is there, for instance, to give Anna a lift when her motorcycle breaks down in the rain. And he is also there to help dispose of the man killed in the barbershop, a murder Kirill had rashly ordered. Handling the frozen corpse as neatly as his nickname ("the undertaker") would imply, Nikolai carefully snips off fingers (a sight Cronenberg is kind enough to share with us) and smashes in teeth (a spectacle we are spared) to make sure it will not be identified.
Having proven his value and discretion time and again, Nikolai gradually moves toward the center of the plot, as designated go-between for Semyon and Anna in their negotiations over the diary, and as custodian of Kirill's frequent excesses. Ultimately, Semyon initiates him into the vori v zakone ("thieves in law"), the Russian equivalent of becoming a "made" man, a process that requires the addition of stars on chest and knees to Nikolai's already extensive tattooing. But neither the initiation nor Nikolai himself are quite what they appear to be.
I would describe Mortensen as a revelation in the role, had he not already demonstrated what he was capable of in his previous collaboration with Cronenberg, A History of Violence. As he did then, Mortensen shows himself more comfortable with darkness and ambivalence than he ever was with the gaudy heroism required of a king in Middle Earth. His Nikolai is an enigma, an evidently decent man surrounded by, and comfortable amidst, heinous evil, one whose motives, at least initially, are unclear. It does not hurt that, alone among the multinational leads, he manages a persuasive Russian accent--nor that, with his extraordinary looks (those cheekbones could have been cut by a jeweler) and athlete's physique, he all but demands the camera's attention.