The series is good until the 7th episode, however, some parts of the storytelling are trivial enough. Some examples:
the boys are running away without asking help in a scene;
one of the means of the boys goes faulty and the other protagonist makes nothing to approach the others in order to simplify their escape;
However the plot in general has a strong structure and a good narration at least until 7th episode.
There are many fights which are cruel enough. Some kind of excessive kindness inexplicable in cruel moments which degrades in servility also against villains. In this case the characters seem too much stereotyped unable to change their attitude.
Last episode is sufficient if not mediocre. Just as example: a villain could kill a kidnapped person although wounded but escapes suddenly albeit has the time to kill him. This example highlights a poor script. Indeed, it seems that the story is based on forced circumstances and forced happy moments. Also the involvement of a minor character in the fight seems out of context.
Moreover, last episode suffers a storytelling rather simplified such as the introduction of some sporadic funny moments and funny character as well, which contrast with the brutal context.
I believe that this series deserves a sequel but improving the quality.