This film doesn't allow easy reviewing because it has many aspects, many ways to look at. Is it thriller? Comedy? Drama? Societal critique? It's all of it; and therefore none of it. All in all, I was underwhelmed and mildly frustrated.

The style is there, I grant it. Cinematography is great. Acting is awkward at some points, but it's OK because of the partially comedy-like nature of this film.

But then, there is a problem with story telling. It builds up nicely toward the middle, where the parasites settle in their host and discover the secret down below. And then it makes an unexpected turn. It's alright to make a surprise at the end (I'd even say it's good), as long as it flows reasonably from the preceding story line. A reveal must make sense once it is revealed. This one didn't do the job convincingly for me. We are given very little clue about why people acted the way they did at the birthday party.

This film is just fine, but no masterpiece in my opinion. Some films are so easy to understand to the point of being insulting; others are so obscure to the point of being pointless. Great films do it just right somewhere in this spectrum. Unfortunately, this one is leaning to the pointlessness.