The thing about trains is that they only go where the tracks go. Usually it's more or less a straight line from Point A to Point B. There aren't twist and turns along the way—just a very linear sense of time. That makes thrillers set on a train all the more interesting because the story is always filled with twists and turns, even if the ride is not.

Transsiberian is the story of Roy and Jessie, a couple who have been on a mission trip to China but who are taking a long way home, riding the Transsiberian railroad from Beijing to Moscow. They end up sharing a compartment with Carlos and Abby, another Western couple. They form a bit of a bond as they travel. Roy misses the train after a long stopover. Jessie gets off at the next stop to try to find out about him and Carlos and Abby wait with her. We begin to find out more about all these people—and some of it is not flattering. From here the story involves smuggling, murder, corruption, torture, and lots and lots of lies. Jessie especially relies on lies as the story progresses. As the police detective says, "With lies you can always go forward, but you can never go back." The more Jessie lies, the deeper she gets into danger as the truth keeps coming out.

Jessie is the real focus of the story. She has a very dark past. She married Roy because he showed kindness to her, when she felt she deserved none. She hasn't really made Christianity her own; she's just along with Roy. She and Roy have marital problems, in part because she still is that person from the past. She tells him when he nags her about smoking, "If you kill all my demons, my angels may die too." Roy seems to have a good understanding of Christian life and tries to serve as a moral compass.

Roy and Jessie really aren't opposites, but they are two approaches to life. One is pragmatic—doing what you think will work for you; the other a stricter black and white. The opening scene (Roy and Jessie in a mission wrap-up meeting) features a speaker saying that in their world there aren't grays, there is black and white—while we see the photographs Jessie has taken during their work. That struggle between black and white, or the many shades of gray, underlies the way they respond to the troubles that confront them.

That black/white/gray struggle also plays out in the other characters. We may think we know who are good guys or bad guys in the story, but there is always something coming up that paints them in a new way. We don't see anyone who is pure in the story.

Christianity has a background role in the film. Not just because Roy and Jessie have been taking part in a mission trip, but because that gives us an insight into Roy's thinking of how things should be. Christianity also comes a bit out of the background in a very pivotal scene that takes place in the ruins of a rural chapel. The chapel is both beautiful and decrepit. The faded icons look down on what happens, but can do nothing to stop it. That chapel is a reminder of what becomes of faith that is not cared for. It still seems beautiful, but it is no longer a force in people's lives.

In the end, the struggle between Roy's black and white view and Jessie's world of grays will have to be settled. At the end of all the twists and turns, Roy and Jessie have to be together in their approach to the dangers they face. Will they follow Roy's moral compass or Jessie's pragmatism? And are they better for their choice or does it wear down on them like the elements have worn down the rural chapel?

The train goes from Point A to Point B, but the lives of the people on that train take many routes and often end up in different destinations.