I saw this Korean movie years ago but my trip to the cinema tonight reminded me of it because there is just a single sudden fright in the movie and everyone in the cinema leapt, popcorn flew and a few seconds later everyone was nervously giggling and apologising to the complete stranger next to them. A great movie. It turns out it was remade as The Uninvited which was out a few months ago. From the reviews I can find, they made a pig's mickey of it. Ah well.