This thriller builds suspense so cleverly that even its most innocent scenes come to portend peril. Of course, any movie set in Siberia may do that for me, especially when it offers the possibility of freezing to death in the snow-covered expanses through which a couple of American kids and their rather dodgy compartment-mates are traveling. Particularly effective is the contrast between the icy vastness outside the train and the sweaty crowdedness inside among the vodka-swigging natives. The fact that most of the Russian characters speak no English leaves the protagonists and the viewer with few verbal clues as to the true intentions of the Russians, thereby heightening our uncertainty as to who's friendly and who's not.