PARK CITY, Utah — A pivotal moment in the new thriller “Transsiberian,” which made its premiere last weekend at the Sundance Film Festival, occurs when an American couple (played by Woody Harrelson and Emily Mortimer) meets a hard-eyed cop (Ben Kingsley) on a train traveling across Russia. Shrewd and educated, bristling with charm and menace, Detective Grinko offers his new foreign friends a concise modern history of his country: “We were a people living in the darkness. Now we are dying in the light.”

Brad Anderson’s suspenseful tale of innocents abroad is not the only film at this year’s festival to explore Russia’s difficult transition to the post-Soviet era. In fact, in a year when the absence of Iraq films has been one of the big stories at Sundance, Russia has emerged as the program’s most prominent foreign country. No fewer than four titles this year — tellingly, only one of them actually produced in Russia — approach the country’s growing pains from different angles, offering a thorough portrait of a nation in which corruption, violence, cynicism, and despair mingle with a weak twinkle of hope and the shreds of a once-lively folk culture.

Utterly bleak surroundings are a common theme. The Russian countryside consistently appears to be full of Soviet ruins and sloppy hovels, and sealed with a heavy layer of mud or snow. “Transsiberian” opens on a murder scene (knife to the skull) in the gray port city of Vladivostok, and as the Moscow-bound train leaves behind the green hills of China for Siberia’s snowbound villages, everything — including the faces of the passengers — takes on a more forbidding air.

The two documentaries about Russia at the festival, “Alone in Four Walls” and “Durakovo: Village of Fools,” share two motifs: heavy gates closing, and the barking of dogs in the night. The former, directed by Alexandra Westmeier, a Russian former television journalist, is an engrossing study of boys doing time in a home for juvenile delinquents. Guilty of crimes ranging from theft to murder, the boys — many of them prepubescent — lead an austere but well-structured life far from their parents. The film’s most compelling, and perhaps saddest, revelation is that many of them actually prefer it that way. One startlingly self-aware inmate says he lacks the discipline to study at home; another is pleased to eat well and not be abused. In the idle, alcoholism-ridden hinterlands of post-Soviet Russia, facilities such as this one may be the closest things left to social services.

Whereas we only hear dogs barking in “Alone in Four Walls,” in “Durakovo: Village of Fools” we see the kennel of ferocious canines kept by the mayor of the Russian town of Durakovo within his walled compound. Like Ms. Westmeier’s film, Nino Kirtadze’s examination of the fascist microcosm Mayor Mikhail Morozov has built on the ruins of Russia’s failed Western-style democracy suggests that the disastrous free-for-all the country went through in the 1990s has caused the pendulum to swing back in the other direction — in this case, way back. A distasteful dumpling of a man with a passion for hot tubs and giving orders, Mayor Morozov has restored the “vertical of power” of the tsarist era — in which a ruler stands between God and the commoners — to everyday life. “Equality on Earth doesn’t exist,” he tells his obeisant citizens, adding that the fall of the Iron Curtain has “only bred disaster and lawlessness.” There is no TV or radio in Durakovo, no new residents are admitted without the mayor’s approval, and all letters traveling in or out must pass through his hands. Ms. Kirtadze’s powerful, slow-building film might sound like little more than an exotic novelty, but her subject’s alliance with national authorities — including the vice-speaker of Parliament, who hails Durakovo as “a symbol of national revival and recovery” — makes her film chilling proof of the resurgent authoritarianism in Russian politics.

In “Transsiberian,” brightly painted matrioshka dolls are vessels for smuggling heroin, an abandoned church the site of a murder. Anna Melikyan’s “Mermaid,” the festival’s other feature film set in Russia — and the only film here with its opening credits in Russian — makes the decay of the country’s folk culture an even more prominent theme. For better or worse, the mode is magic realism. Alisa (Mariya Shalayeva) is conceived when her full-figured mother emerges nude from the sea — a 200-pound Venus — in full view of a loitering sailor; her aquatic origins give her the occasional ability to make her wishes come true. And so, when she realizes her father will never come back to the beachside shack she shares with her mother and grandmother, she has a hurricane blow it to smithereens.

The family moves to Moscow, where Alisa gets her first taste of the cynical, crassly materialistic place commonly called the new Russia. Having been rendered mute by a solar eclipse, she’s an outcast who observes this glossy, confounding new culture more than she participates in it. Ms. Melikyan’s modern fairy tale aspires to be something like a Russian “Amélie,” but its erratic protagonist (despite her wonderful smile) is not as endearing as she should be, and the film never finds a comfortable rhythm. And the force of Ms. Melikyan’s show-stopping images is dulled by the overwhelming sense of contrivance.

Alisa falls in love with a man (Yevgeni Tsyganov) who has gotten rich selling real estate on the moon, a witty comment on commercialism’s ever-expanding frontiers. There’s also a ubiquitous household-appliances brand called Evolution, and lots of double-edged advertising slogans, such as “Don’t Be Afraid of Your Desires,” from which Alisa takes cues. All these clever ideas don’t amount to a great film, but “Mermaid” represents a spirited, if somewhat confused, resistance to the onslaught of money-driven foreign concepts that has reshaped urban Russia in recent years.

Ms. Melikyan’s artistic sensibility leaves no room for the question of social programs or law and order that the other films address, and in some ways it is the least optimistic of them all. (Of course, this may depend on the nationality of the viewer. “Transsiberian” comforts American audiences with the portrayal of a helpful embassy in a hostile land, which Russian viewers may find all the more embittering.) Ms. Westmeier, on the other hand, sounded what might be described as a hopeful note in an interview with the Sun earlier this week. Russians are starting to “understand that you need to build your life,” she said. In the final scene of “Alone in Four Walls,” the camera surveys a dormitory room just before lights-out. One of the boys is sleeping, another is reading, and a third is crying into his blanket. In the Russia depicted on Sundance screens this year, that’s about as optimistic as things get.