The film is back to being a prequel, focusing on Katie and Kristi when they were little kids. They have a skeptic mom, and a dad who looks suspiciously like Micah from the first film. He's a videographer and he likes to record things all the time (like the first two movies) and after an earthquake erupts, he discovers that an invisible figure emerges from the dust. So naturally, he wants to keep recording to find out what it is, and what he discovers is that its an invisible friend named Tobi who has some connection with the little daughters.
Upon watching Paranormal Activity 3, it felt like there was a board meeting after the second film and they listened to all the bad-mouthing, spoofs, and also took in an account of what scared people (prepare for an homage of the kitchen scene of the second film) and culminated all of this together into an Alchemy Pot and born what could be the scariest film to date. The theater I saw it with was screaming at all the scary parts, especially when the demon terrorizes the little girls; all the way up to a tension filled ending that left many not wanting to look at the screen. The filmmakers knew how to use timing and tension to generate the scares, and that's really the fun of these movies. It's the tension building and the creative payoff on what they provide for scares. My friend said it best where she said, "It was like a roller coaster ride that I couldn't get out of." It's really that intense.
The only thing that sucks is that some of good parts in all the trailers didn't make it to the final cut. I'm hoping for an extended release on the DVD like they did with the last film because it will make it that much more exciting. Seriously, forget your complaints from the last two films and give this film a go. There is a lot of fun to be had, and it's a great way to celebrate Halloween this year.