It was released in theaters on April 1st, 2011. It was made by the same guys who did Saw and Paranormal Activity. I thought the first Saw movie was pretty decent, the rest of the Saw films are awful. I hate Paranormal Activity, terrible film. So the two combined made a film that started off decent and then turned terrible.
Everything starts off ok. Despite the biggest cliche in horror of a family moving to a new house, the build up is pretty creepy. One of the kids, Dalton, falls in to a coma after falling off a ladder. It is suggested he fell due to seeing a demon, i think he fell because he realised his name would get the shit kicked out of him at school.
Some months later, Dalton is taken home, still in a coma. He has his bedroom set up with all the necessary equipment and his parents stand around his room in a melancholy fashion. Shit starts going down. The mother starts to see figures and people in the house. These are the best scenes in the film and really are unnerving. Then they decide to explain the whole story of why the demons are stalking coma boy and ruins the movie.
All the mystery and spooky aspects of the film are taken out of it because every last detail is explained and it becomes incredibly predictable because of it. I could see what was going to happen about 30 or 40 minutes from the end. On top of that, it was a complete rip off of Poltergeist. The only good moment of the second half of the film is an old woman having an orgasm in a gas mask. Something like that anyway. It was unintentionally hilarious.
In summary, the first half was not too bad with some pretty creepy moments, the second half went so far downhill that the first half needed binoculars to see it.
Oh, and i know it's been said before, but....
Insidious demon looks like Darth Maul from Star Wars: The Phantom Menace.