This was a fascinating insight into the world of those who attempt to foil indiscriminate attacks on French soil. On fact, it didn't varnish the truth but showed the tensions between the DGSI and the DGSE (the internal and external security services) and how their operational imperatives differed sometimes to the point of sabotaging each others' actions and contacts.
The series is written mostly from the point if view of the "goodies". There's very little airtime given to the baddies and their possible motivations and actions. And, as has been pointed out, the series is dialogue driven; there's very little action. That's not a flaw as it engaged the mind in an intelligent manner.
As a testament to the work of those who keep France safe it was a fitting tribute. I recommend it.