Seeing the words "based on a true story" in a trailer for a horror movie is fairly commonplace, but director James Wan wanted to make them mean something in The Conjuring. Warner Bros. and Wan stood by their claim when they came to WonderCon Anaheim, opting to bring the real-life people The Conjuring is based on to represent the film instead of its stars.

"One of the things, as I like to say, is nowadays people are so used to seeing movies that have the tag 'based on a true story' to the point that no one really takes it seriously any more, or people just roll the eyes, but I didn't want it to be that," Wan told Spinoff Online. "I wanted it to be a banner that I would be proud to wear on my film, and so I tried to honor and stay as true to what they say happened to them as much as I could."

In the New Line release, Patrick Wilson and Vera Farmiga play famed paranormal investigators Ed and Lorraine Warren, who are called in 1971 to a haunted Rhode Island farmhouse believed to be inhabited by several ghosts, including that of a witch who has imprinted herself on the family.

Lorraine Warren gave The Conjuring her stamp of approval, saying, "I'm happy that I had the opportunity to explain it to people, and having that opportunity is very important." She added that it was "very important" for the story The Conjuring to be told as accurately as possible.

That said, The Conjuring condenses events that took place over 10 years into a two-hour movie. Cindy and Andrea Perron, two of the daughters who lived in the house where the events of The Conjuring took place, said a lot got left out of the film, but it can still wear the "based on a true story" banner "proudly." Producer Walter Hamada said viewers might be surprised by how The Conjuring plays out, as the fact the Perron sisters are still alive proves that everyone doesn't die at the end of the movie.

"It isn't a film about how many people die. It's about the horror of living in that house and the experiences they went through," he said. "It is a movie that I think does surprise audiences because you walk out feeling good but also feeling scared because that stuff is there and it's out there."

Best known as the man behind the first Saw, Wan is coming off the hit movie Insidious. Like Insidious, The Conjuring also stars Wilson, whom Wan calls his "lucky charm."

"I'm just going to put him in all my movies even if he's not the lead in them," the director joked. "I'll just put him in the background walking by. He'll be the ghost."

While Insidious was more of a "fantastical" film, according to Wan, The Conjuring is more grounded in reality. He said the slow burn that viewers saw in the trailer is indicative of the movie as a whole.

Wan was a fan of the Warrens before he was pitched The Conjuring, and said that was a big draw for getting him on board. "When the chance came after Insidious to do a studio film -- and, you know, obviously I couldn't leap into my romantic comedy that I want to do just yet, no one was going to give me one of those movies right off the bat -- so I knew that my studio film would have to be something sort of in this world, but I didn't want to sort of rehash myself even though it's a ghost story again," he said.

Yes, you read that right: the director of Saw and Insidious is desperate to direct a rom-com. "I would love to," Wan said. "That's one of my favorite genres to watch, so I would love to do that one day. I would love to do a film like Swingers, that would be great -- with Patrick Wilson, yes."

As for the status of Insidious: Chapter 2: "I'm in post[-production] right now, cutting it. Like, knee-deep in post," he said. "The movie is a direct continuation of where we left off. It picks up right after it, so if people love the Patrick Wilson and Rose Byrne and Barbara Hershey storyline, it's basically that. But it kind of opens up on the mythology a bit more about who this entity that has been haunting Patrick's character his whole life [is]."

Just don't expect Wan to get on board with more Insidious sequels farther down the road. "If it does [happen], it's probably not with me,” he said. “We'll see.”

The Conjuring opens July 19.