I read on the forum that the reviews for this film are suspiciously alike and might even come from the same source close to the production. So, I'm here to tell you that doesn't really matter, because the movie is good and it is very much worth watching.
I went into it completely unarmed. The only thing I knew was the title and the fact that they spoke Spanish. The genre hit me on the head pretty much off the bat and I was happy with it. (Films from Spanish spoken countries have a good tradition in that respect.) I strapped in for the ride and boy was it a thrilling one! I found the movie to be refreshingly good. Not wanting to give away anything (I wish everyone the experience I had), I'll just say that for me it was the engrossing story and the flawless direction that did it. I was completely sucked into the narrative, but as usual I thought I had it all figured out pretty early on. And then I was forced to piece together a new explanation basically every 10 minutes. Which was in itself awesome. Looking back I now see they had me right where they wanted me all the way through the film and right until the very end, hit every cue, killed every mark.
As mentioned, the directing is perfection. (Which means I am now very eager to see more from this Mr. Alejandro Hidalgo!) It's hard to avoid the cliché moves, once within the confines of the specific genre and we've all got pretty much desensitized to those ever-repeating scenes. Well, prepare to change your mind! This will make you see that, if done by a skilled hand, they have not lost their power at all. In fact they work better than ever...
The acting was good too. I especially liked the mother (Ruddy Rodríguez) and the children. There were some scenes where I found it to be a bit telenovela-ish (over the top) - mostly scenes involving the Priest -, but, to be fair, I am very prejudice in that respect.
So, to sum up - and not say anything at all - I enjoyed this movie very much and I highly recommend it. I also strongly recommend finding out why on your own - you'll be grateful for the gift!