The most shocking thing about summer's scariest movie – the Poltergeist-style haunted-house flick The Conjuring – might just be how gore-free it is. Even though there's no sex, foul language, guns or much violence of any kind, it still earned an R rating. "They asked if there was one scene or anything we could cut to get a PG-13," says Patrick Wilson, who stars in the movie alongside Vera Farmiga. "They said the rating was literally just due to a feeling. They thought it was too terrifying."
Even more surprising? The director is James Wan, the Malaysian-born torture auteur behind the Saw franchise. "I made Saw to get people's attention, but I didn't realize how successful it would be," says Wan, 36. "I wanted to show that I could make a scary movie that doesn't rely on the shock factor of blood and guts."
The Conjuring – which has an excellent 88 percent positive rating on Rotten Tomatoes – is about a real-life family, the Perrons, who moved into a 18th-century Rhode Island house in 1971. (It comes with a "based on a true story" tag.) Things immediately get really, really unpleasant – from the unexplained death of their dog to ghosts that yank the children out of their beds. Looking for help, they call paranormal investigators Ed and Lorraine Warren, who later became famous due to their involvement with the Amityville Horror.
One of Wan's favorite scary movies is Jaws, and like in that Spielberg classic, the monster isn't even seen until near the end. "I think that's a lot scarier because your imagination tends to fill in the blanks," he says. "A character can be staring up into the darkness behind a room door and you just see the fright on their face. That's scarier than showing you what's behind the door."
This story is from the August 1st, 2013 issue of Rolling Stone.