I can't resist writing a review for this movie :P Small spoilers ahead.
First of all, this movie 'reunites' 3 actors from Paco's Men (a very funny TV series), Hugo Silva, Mario Casas, and Pepón Nieto. Who has seen the series, will surely love that. Second, it's a horror-comedy by Álex de la Iglesia, which should, by now, be enough for you to want to see it. He's made some very good movies, and some crazy as well (The Last Circus).
The story is about two guys (out of few) who commit robbery, one of which brings his son with him. They manage to get a bag full of golden rings, and they hijack a taxi, because the second guy's woman took his car in front of them. Things get a lot worse from there (and I mean it in a good way), where the boy's mother is included, 2 police inspectors, a taxi driver & passenger, and of course, a bunch of meat-hungry wanna-raise-the-queen-of-whatever witches.
Tbh, it's not really a big spoiler, but basically a description of the movie. Anyhow, considering that two of the main actors are rather.. famous, and very good, then that there is Carolina Bang acting as 'rebelious' witch-daughter, and her sinister, wicked, yet atractive smile, then the fact that there is a lot of comedy, I'd say this movie is great, or at least as good as horror-comedy movies can get. In fact, a lot of movies try to be as good as this, and fail, where this one succeeds. All in all, I recommend it. If all of this is not enough to get you to watch it, check one of the trailers (the shorter one especially), and if you're into crazy, at times over-the-top movies, you'll surely like this.