27 horror films that will actually terrify you Paranormal Activity (2009)

Directed by Oren Peli

The only film I’ve ever watched where I considered switching off halfway through out of sheer terror. The tension ratchets up endlessly as the ‘found footage’ style adds to the claustrophobia. A decision was made long ago never to watch it again - Tom Embury-Dennis

Or: a cautionary tale for leaving your leg dangling out of your bed. Injecting fresh life into the found-footage formula, the first Paranormal Activity managed to induce chills the world over by the simple - and rather frugal - use of a static camera set up by couple Katie and Micah, all in the hope they can learn what's going 'bump' in the night. With every new nighttime scene - each displaying more demonic hauntings than the last - your sounds of terror will become more audible. - Jacob Stolworthy

Available on Netflix