I don't know what people expect from thriller/horror movies if they are willing to call this one tragically bad or "lame". Not all thriller movies can be the best - and this one is not one of the "best" you'll ever see. But that's no reason to slam it quite so badly. There have to be a bunch of movies that are in the average range, obviously, not all movies can be the best. This one is definitely in the average range - BUT it's one of the better "average" thrillers you'll come across. The reason it's in the upper levels of "average" is because it's directed by the Pang Brothers. They are responsible for The Eye and Bangkok Dangerous and their brilliant stamp is all over this little thriller. Take notice of how beautifully framed each scene is, the effective use of silence throughout, the play on colours & textures, the minimalist dialogue etc. It's beautifully filmed and well acted by all but the mother character and it creates a lovely tense atmosphere with plenty of scares and spooks (but no blood and guts - so that will "disappoint" some). The biggest problem with the movie is the screenplay itself. It's not the most riveting story in the world & the plot has several flaws (like so many thrillers do). But it doesn't matter, in the hands of the Pangs this taut little thriller still a far better movie than most and easily worth the rental. Just don't go into it expecting the next best thing. It is what it is. An average but gripping movie.
