Lake Mungo doesn't approach it's story from the "found footage" perspective, but instead is essentially presenting itself as a documentary chronicling events after they've occurred. This isn't trying to be Paranormal Activity or The Blair Witch. And it's probably in part because of that difference that the film works pretty well.
The story in this little Australian fright flick is about a family whose daughter drowned while they were on vacation together. The mystery though, isn't about whether there was some kind of foul play, the central question or tension to the film is the fact that they start experiencing the kinds of things that are usually associated with a haunting. They tell of sounds in the house, coming from the girl's bedroom, etc.
I don't want to give anything away beyond that, but I can tell you that on a number of occasions during the film, I was definitely surprised by the direction the story was taking. In being able to pull that off, they do a wonderful of giving you some connection to the way this family must have felt as these events were taking place. The best word I can use to describe the construction of the story, and the cinematic presentation of that story is elegant. This isn't something that's trying to make you jump out of your skin.Though there are some really creepy visuals in the film, it's intent seemed to be more to give you a consistent feeling of unease, and to creep you out once you've gone home and you have to turn out your lights at the end of the night. It's a very subtle, subdued film that succeeds in creating an atmosphere that induces the fear of the unknown in a more cerebral way that most horror films today don't have the patience or skill to even attempt.
It's not for everyone, and when it was released by After Dark Films as one of their Eight Films To Die For in their yearly traveling Horrorfest, it got mixed reviews, and was more or less passed over. I can definitely understand the horror community not being thrilled by it because it does eschew the kind of shock and gratuity most horror fans have become accustomed to.
I'm not going to recommend you try and watch this immediately (though it is on Netflix, Watch Instantly), but the next time you're looking for something to watch that is well made, isn't too heavy and some creepy fun Lake Mungo would do well. This is a good one to add to the Halloween viewing list as well.