But I wouldn't necessarily call this a horror movie. I put this under a sub-category of horror called Dread. Examples of great Dread movies are "The Birds", "28 Days Later", and "The Ring". These are scary movies that do as much with overall atmosphere as they do with scare tactics. They usually slowly build tension and fear and an overall feeling of "Oh my god we are so fucked." The meat of the movie is more in that feeling than in any plot device, quick jolting camera angle, scary music, etc. It's all about atmosphere.
We start with a storm, a wonderful way to begin the dread. Then there is calm because it's important to have plenty of calm in between the storms in order for that nice juicy dread to sink in. The father and son, who are the main protagonists in this movie, are outside the morning after the storm with the boy's mother and they notice a mist coming down from the mountains across the lake. It's an eerie image and we slowly feel that pit in our stomachs. The foreboding builds. As the father and son ride into town large numbers of army trucks race past them away from their base on the mountain. When they are inside the supermarket fire trucks and police cars race by. Something is wrong. Then comes the siren. Nobody moves and everyone is suddenly silent except for a haunting siren, similar to an air raid siren. Everyone is still because the town siren only sounds when something is really fucking bad. The siren in this movie is one of my all time favorite moments of sound in a movie because so much is said in just one simple ominous sound. Now something is seriously wrong. As the siren is sounding a bloodied man comes running towards the supermarket, visibly terrified, and yelling about something in the mist which we can now see enveloping everything. The doors in the supermarket close once the man comes in and the people inside begin to realize that something terrible is on the other side of that door. We have a moment where everyone is panicked and beginning to feel really fucking freaked out and then the whole supermarket begins to shake as if there is a large earthquake. Aaaah Dread.
The great thing about the perfect dread is that once you've built it it's there until the end. The rest of the movie is just marinating in it. In "Jaws" we didn't see the shark until about 2/3 of the way through the movie. Through pacing, camera angles in the water, sound, and story, a dread was created without even seeing the shark. We are more afraid of that which we can not see as long as we can feel its impact.
Don't get me wrong. Their are creatures. We don't see most of them until at least half way through the movie but they are wonderfully creepy and magnificent. We have monstrous bugs, terrifying spiders, flying pterydactils from hell and an awe inspiring tentacled beast at least 100 feet tall taken right from the pages of Lovecraft. Dread doesn't work if there is nothing to dread.
The characters also seperate this movie from most movies of its kind. We have a living, breathing community that makes everything more real, and we have people that we genuinely care about. The movie takes its time and we get to know about the father and son, the school teachers, supermarket employees, etc. We have less music and more slow, quiet moments of conversation that build the characters and the overall mood. We are truly in the middle of these moments where gradually everyone begins to realize that this could be the end of the world.
There is a very interesting aspect to this movie that goes against convention. Throughout almost the entire movie we encounter a woman named Ms Carmady. We are led to believe that she is a religous fanatic and just a little bit crazy. We are taught as viewers to see her as an evil force but by the end we realize that everything that she has predicted has come true. "It's death out there". "They'll come at night and take another". Everything that is happening is straight from the scriptures she keeps talking about. A storm, smoke, a beast, locusts, spiders, sacrifice, particularly the sacrifice of the only son of Abraham which comes into play later. We realize by the end that this supposedly crazy woman, seen as a monster herself, may actually have been the voice of reason and truly there to help these people. We realize that this may be a movie about facing monsters instead of running from them. Everyone who tries to run away, except for the father, ends up dying, and we know that he ends up suffering the most in the end. When someone dies or is sacrificed (at the willingness of Ms. Carmady) the monsters go away for a while. Those who stay in the supermarket like Ms. Carmady suggests end up outlasting this apocalypse and those who try to outrun it end up failing. I'm not saying that this is the point of the film but it's an idea that makes this movie so much more complex than others of its kind.
This movie will be remembered most for its shocking ending so i'll end there. The father, son, and three other main characters decide to make a run for it at the end. They drive as far as they can before the gas runs out. They see horrible things. The father sees the dead body of his wife wrapped in a giant spider web, they see cars overturned, telephone poles decimated, they hear horrific beastly sounds in the background, and see a 100 foot tentacled monster walking in the distance, it's every step quaking the earth. The car runs out of gas and the father has a gun with four bullets left. The car sits still, terrible sounds surround them, and there has been a non-verbal agreement that rather than being taken by the monsters he will shoot them and put them out of their misery, his son included. He finishes the deed, but with only four bullets in the gun he is left to suffer the death of his son. He screams in rage, gets out of the car, pleading with the monsters to come and end this. He hears growling coming towards him and prepares himself to be torn apart. As it gets closer he realizes that the mist is fading, going away, and these aren't monsters but tanks and helicopters cleaning up the mess and transporting the survivors. The world hasn't ended and his real suffering begins.
This is the kind of ending that knocks you on your ass and stays with you long after you leave the theatre. It's an ending with fucking teeth, that kind of destroys you and fills you at the same time. I adore the ending of this movie for the incredibly powerful emotional punch and also because it gives the movie such a multi-layered theme. Is he being punished for trying to run away and not being willing to suffer god's wrath? Is he being punished for not having hope that this would end? Has the world been spared because he has sacrificed his only son like Abraham's in the scriptures? Is he a Christ-like figure who has now suffered monumentally so that the world can move on? Whatever the case, it does that thing that truly great endings do. It takes the experience to another level and makes everything that came before it more powerful and more complex.