Briefly said, this is Alain Corneau's third attempt - after Police Python 357 and Choix Des Armes - to create a Film Noir in the manner of Jean-Pierre Melville. An like in the other two films, his attempt was (more or less) successful. Like his idol, he is very good in selecting the right locations and creating a mood of nightly jeopardy. The greatest difference is his lack of trust in the pictures which often results in unnecessary dialogues. But apart from that, Corneau was the only director who really managed to get close to Melville. And from his three crime movies, this is surely the best one - if you don't think of the first 30 minutes of Police Python and the last 30 minutes of Choix. It would be interesting to know, why this is the one which is practically nowhere to be seen.
PS: As another funny example of German renaming, this one was called Blues Cop.