Is The Last Exorcism the scariest film ever?

He is notoriously associated with so-called "torture porn" movies, but producer Eli Roth's new project is a chilling, religious horror film.

The Last Exorcism tells the story of the final job of Reverend Cotton Marcus, an evangelical minister in Louisiana who specialises in exorcisms.

For Roth, horror movies serve an important purpose, allowing viewers to let go of built-up emotions.

"We do have all these feelings that we bundle up our whole lives, and when you watch a scary movie you're able to release them." he said.

The Last Exorcism opens in cinemas nationwide on Friday 3rd September.