In the first leg it has a lot going for it. The cinematography is great, and as much as they attempt to make things dreary, this thing could really function as travel vlog for Thailand. The faux doc style brings a realism to the mystic elements and it feels like a unique backdrop for a horror flick. The setup is slow but enjoyable and you begin to wonder if it's ever going to erupt into full blown horror. Rest assured, it does. However, with the quality of the preamble, you grow to believe the film had something more clever up it's sleeve. What you eventually get is a rather run of the mill possession tale, and things sort of fall apart from there.
Where the mocumentary initially lent credibility, it eventually devolves into the common found footage problem of "why would a real cameraman actually be filming this?" At one point reaching the height of ridiculousness where a girl has a mishap with her period and the camera follows her to the bathroom, like a psychopath. The possession element does little to set itself apart from it's many contemporaries, aside from forgoing the regular Christian/Satan angle. Narilya Gulmongkolpech's performance is enthusiastic but is often reminiscent of haunted house staff doing the crazy/scary routine. The whole thing seems to overstay it's welcome a bit, which is strange because the slow build seems to breeze by and it's only when things heat up that they start to feel redundant.
I don't want to be too hard on it, because it's in many ways a well made picture, it just doesn't live up to it's own potential.