> Buy Paranormal Activity 3
The threat of demonic spirits is scary enough, but when your castmates turn on you to ramp up the shocks then you know you're in trouble!
In the clip above, Christopher Nicholas Smith hatches ingenious ways of frightening his co-star Lauren Bittner.
Alongside the prank video, the Blu-ray will feature the original theatrical version of Paranormal Activity 3, an unrated cut and the 'Lost Tapes', which reveals footage not seen in the film. The DVD contains the unrated version and a digital copy.
> Paranormal Activity 4 confirmed for pre-Halloween October release
> Watch the Paranormal Activity 3 trailer