I really didn't know what I was expecting from this. I've actually seen some excellent stuff coming out of Chile recently, but this wasn't of the same standard.
It's pretty clear that the venal and incompetent local police department didn't cooperate in the making of this series, so much of each episode had to be invented. Unfortunately, a lot of it felt like padding; the series could have been resolved in 4 episodes.
The love affair between two of the main protagonists looked contrived. Worse there was clearly no chemistry between them. Their lovemaking scenes were utterly unconvincing.
I presume the discovery of the murderer happened as outlined in the series. This was portrayed as an intuitive leap of faith rather than the following of a set of clues.
We shall never know. The files relating to the cases of the missing girls were burnt and incompetence and corruption were covered up. I guess this effort was the best that could be done with the material available but it's not really up to par.