The classic Hitchcock plot of sneaks on a train gets an engrossing revival in "Transsiberian." Writer/director Brad Anderson gives us an artful, shifty-eyed take on human strengths and weakness; his film delivers the pleasure of a conventional tale well told, with clever twists and complex characters.

Woody Harrelson and Emily Mortimer bring humanity to their roles as Roy and Jessie, married American missionary volunteers returning from China. The six-day ride from Beijing to Moscow puts the pair in a neo-noir nightmare: They don't know whom to trust, or even if their own actions are right or wrong.

The couple's trip to China wasn't entirely charitable. Roy thought an adventure would be good for his cooling marriage. Before settling down with her nice, dull husband, Jessie was a self-destructive alcoholic. Roy, a train nut, figured that what excited him would thrill Jessie, so he booked their return by rail, a journey she endures with a wan smile.

Her interest picks up when an attractive young couple, Carlos and Abby, come aboard. Carlos eyes Jessie with more-than-friendly interest, while Abby remains mysteriously reserved. The backpackers know a lot about faking passports and slipping through customs checkpoints, and it appears they're involved in some sort of shady business. Roy and Jessie become separated (is Carlos to blame?), Jessie leaves the train to wait at the next station and the young couple insist on accompanying her. Soon our conflicted heroine is in touch with the dark side she's spent years trying to suppress.

Anderson is a masterful stage manager of plot, introducing shocks and clues just when they will be most effective. The anxiety creeps higher with each new suspicion, interaction and revelation. He nonchalantly introduces everyday items -- a digital camera, a Russian nesting doll, a bottle of vodka -- that will play crucial roles in development of the story. Even the train's tinny Muzak programming -- sappy '70s love songs -- sounds sinister.

You can never be certain when a turn of events is coincidence or part of some overarching scheme. When the travelers are joined by Russian police detective Grinko, is he truly on a personal trip or constructing some type of sting operation? The longer we observe these deeply developed characters, the less they resemble what they purport to be.

They're not mere suspense-movie ciphers, though. Harrelson has never been so relaxed and natural, and his innocent Midwestern rube is one of the most credible portraits of naïve virtue I can recall. Mortimer, long a sideline delight ("Lars and the Real Girl"), makes Jessie a nesting doll of courage, guilt, pride, fear and vulnerability. Ben Kingsley brings inscrutable intensity to the role of Grinko, a man who has seen Russian regimes come and go, leaving only corruption and opportunism behind. As the shifty backpackers, Eduardo Noriega and Kate Mara are deliciously difficult to pin down.

You may feel certain about your train of thought, but "Transsiberian" will derail it time and again.

Colin Covert • 612-673-7186