Most people have probably heard of the idea that babies and young children can see and hear things that older people can't, or have lost the ability to. That a baby in a crib gurgling and laughing at the ceiling, for example, is actually talking to a spirit there. It's a fascinating premise, whose application to a horror movie is a stroke of genius.
In "The Messengers" a family moves into an old farmhouse where something very bad once happened. Only Ben, the little toddler of the family, can see the supernatural prescences in the house, and he appears more delighted with them than afraid. When his teenage sister Jess also starts encountering unusual occurences - this time of an apparantly non-benevolent nature - she also begins noticing Ben's unusual behavior as well and realizes that he too is experiencing something out of the ordinary; the hard part after that is getting anybody else to take her seriously. The movie utilizes much more atmosphere than action, and the cast has to carry off a lot the show by reacting to very subtle (Most of the time), slow-paced, occurences, in a way that makes it feel real and frightening. The actors and actresses were well picked for their parts, and Kristen Stewart as Jess and twins Evan and Theodore Turner as Ben, playing the characters who experience most of the strangeness in the movie's early, slower-going, parts, are especially impressive. All the production values necessary to make this kind of atmosphere work - the light and shadows, the subtle use of sounds, the camerawork, etc. - are all handled very well too.
In the last one third or so of the movie, as things start to speed up and secrets come to light, I guess you could say that there were too broad directions it could have gone in, that it had to choose from. Myself, I would have chosen the route the movie didn't take, but it handles the path it chooses so well that it avoids slumping into a letdown. (I am still curious, though, what it would have been like if they had gone that other way) It's worth noting that when it ended I was rather taken aback that it was over so quick. Its running time is something like 85 minutes, but it felt like it came it at under an hour - and that's even in light of the slowly building pace it maintained. It must have been doing something pretty right to make time fly like that (on the other hand, I've seen other movies of about the same length that seem to drag on for hours). "Messengers" could have actually been quite a bit longer without hurting itself one bit; and as good as the ending turned out to be it may have been even better if it had gone on that different turn, but there's no point in complaining with something this good. Highly, highly recommended for fans of "Dark Water", "The Eye", "Haunted", "The Sixth Sense", "Pan's Labyrinth" and other atmospheric horror movies. "Red Rover" is another, far less known, movie that also fits great in this vein that you might want to check out.