From the moment I saw the trailer, I knew that this film would scare the bejesus out of me. "The Strangers" stars Liv Tyler and Scott Speedman ("Underworld" and "Felicity").
Since we only have two main characters, we are drawn to them right away. They look like any normal couple. It's nice that they didn't act heroic too. Heck, Speedman's character even lied about his hunting skills.
As for the tormentors, we have 3 people in masks. The first one (long-haired girl) made an appearance asking for somebody who doesn't live there. The director made sure that we don't get to see her face much. There's another girl who is not so creepy. And then there's the creepy tall guy in a home-made mask. He reminds me of Scarecrow in "Batman Begins". The most terrifying scene was when Liv was in the kitchen unaware that someone is already standing behind her in the corner watching her.
In the opening, pay close attention to the 911 call that Liv's character supposedly made. I think it's not the same as the one she made during the film.
One thing that got me is that the villains just drove off (we even got a glimpse of the driver's face). This means that they could do the horrible things again and again and again. Freakin' scary thought!
Kudos to director, Bryan Bertino, for making some of the audience scream in many parts of the movie. I've never been this frightened in a very long time (not since "The Blair Witch Project"). It doesn't help that I'm now alone in the apartment. I would probably sleep with the lights on tonight ;oP