In the vain of True Detective (2014) but with the intensity (and pretentiousness) dialled down a couple of notches. This was compulsive, engaging and entertaining throughout.
I watched with the original Spanish audio and Spanish subtitles so I can't really comment on the quality of the script because my level of understanding was at about 70-80%.
The pacing was even, there weren't any unnecessarily drawn out scenes and everybody behaved in a realistic manner. The acting from the leads was superb but some of the supporting cast were quite wooden and most of the photographs used in the film were extremely posed. Those are minor critiques though; the only thing that really irks me is that no matter how well these films are made, and no matter how sensitively the subject matter is broached, they always feel a little gratuitous, hence why they usually lose one or two points from me. I watched The Treatment (2014) a while ago and both of these films currently have roughly the same IMDb score. Clearly then, ratings are hugely affected by the emotional impact of dealing with sexual abuse and murder. La Isla Mínima was, in my opinion, markedly better than The Treatment and I hope its rating increases to reflect this.
Another reason this film was more satisfying than others in its genre is that the police behave in a realistic manner - granted this is part of the commentary on the culture in this part of the world and what police have to resort to in order to protect their own people, but it still felt satisfying from a plot perspective and as an audience member. The final confrontation was horrific and yet entirely necessary. The film needed it and this was also entirely in keeping with the characters and the message of the film. Obviously, each will take away their own views but for me, the 'very' end made me question my earlier conviction that the final confrontation was 'justified': isn't that what everyone says to justify their actions?
If you enjoy films in this genre then it's an obvious choice 8/10.