It was very trendy in those years to hire American actors :René Clément had done it several times notably for "le Passager de la Pluie" where Charles BRonson played opposite Marlene Jobert.Henry Silva plays the American gangster here, a deserter (he was a marine).His strange face could have been used to good effect ,had he been properly directed.
The director's career essentially consisting of porno movies (it shows in the scene in the private nightclub 'l'Hippodrome" where greybeards play dice (big dice) to "win" the local "bunnies" ),what can we expect from him in the thriller field?Not much and that's exactly what we get.
The gangsters,the firemen and the cops are so naive ,so dumb (the fireman takes the biscuit: six cars are burning but he does not care)one can only regret the director did not make a spoof on gangsters movies like "le Cave se Rebiffe" .But ,with the eventual exception of André Pousse ,all the actors take themselves seriously .The plot has enough holes to fill the Albert Hall ;one example: a dangerous gangster has escaped from jail and the Police do not seem to bother.