Let's get one thing straight: a horror isn't a horror without a Catholic enquiry into demon possession. And, as everyone knows, a horror isn't credible until at least one little girl, costumed in a Victorian nightgown rocking dangerously dilated pupils is found in a kitchen/bathroom/attic. Cue the latest instalment in the Paranormal Activity franchise, which contains not one but two spaced-out girls, lots of biting, hair in places it shouldn't be and possession scenes that will haunt you as you walk back to your car after the cinema. So if you like your movies with a twist of demonic fury, check out the new trailer for Paranormal Activity: Marked Ones now. Or don't... it's your life. (Read: sanity.)