1838. Investigating Magistrate Remy d'Arx is on the trail of the Black Coats. If he isn't stopped, the evil brotherhood of thieves and assassins may well be destroyed. But d'Arx has taken precautions in the event of his death. Only the nearly immortal Colonel Bozzo, the mastermind of the criminal conspiracy, can put an end to his threat by using his most deadly scheme -- the INVISIBLE WEAPON. But dissension grows in the ranks of the villainous society...