When intruders interfere in the robbery of Le Mataf (Michel Constantin) and his gang and a girl is murdered, they are set up for blackmail by an underworld figure who wants them to do a job for him...

After carrying out a flawlessly planned hit, Jef Costello, a contract killer with samurai instincts, finds himself caught between a persistent police investigator and a ruthless employer, and not even his armor of fedora and trench coat can protect him.