Based on a short by Swedish filmmaker David F. Sandberg, Lights Out manages to stretch that three minute film’s barebones set-up into a feature length horror to varying degrees of success. The plot is uneven and the second half would clearly have benefited from veering more on the side of mysterious, but overall this uses the fear of darkness as well as any film ever has. Maria Bello and Teresa Palmer are both excellent, and the film thrives during its genuinely terrifying set pieces, particularly an opening that uses motion activated lights to perfection. With this short and sharp frightfest Sandberg has announced himself as a mainstream horror director to watch.