This is a really enjoyable, strange, low-key horror film from Argentina. Many scenes are filmed in a sickly yellow light, and the horrific prosthetics are often *just* out of focus. When they are dwelt upon, they look truly horrific.
The story, as has been said elsewhere, comes second to the scares – which is acceptable for the most part, because the film *is* scary, both in terms of jump scares and the overriding feeling of unease, which is beautifully conveyed.
The narrative sometimes descends into a tumble, with it being made unclear which moments are being told in flashback, and which characters to invest in. Truth be told though, this might even be deliberate to enhance the delirium.
A terrific film; happily, both a remake and an Argentinean sequel appear to be in the works. My core is 8 out of 10.