Just when it seemed that every shelf in the "alien visitors" library had found an occupant, M. Night Shyamalan has uncovered an unused one for his own use. Although Shyamalan's Signs includes plenty of clues and cues from previous movies about the arrival of our stellar neighbors, his overall approach is radically different from the ones taken by Independence Day, Close Encounters of the Third Kind, Contact, or other similar fare. By limiting the number of special effects shots and treating the film more like a horror movie than a science fiction spectacle, Shyamalan creates a claustrophobic atmosphere and keeps the tension level high. There were times during this film when I was strongly reminded of Panic Room.
It helps that the trailers don't give much away. Although Signs doesn't have a "surprise" ending like The Sixth Sense or Unbreakable, nearly everything about the aliens is shrouded in mystery - their appearance, their intentions, and whether they're friendly or hostile - and it's better that these things are discovered through the viewing process, not beforehand. I don't know who was the primary architect of the commercials and trailers, but they have done an effective job of teasing the movie without revealing anything critical. Aside from there being crop circles, aliens, and Mel Gibson, we don't know much.
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