Agitator (2001)

The Japanese director Takashi Miike is a true maverick and a prolific one at that.  Since coming on the scene in the early 90s, he has made dozens of feature films and television movies and taken a number of cameo roles in both his and other's films.  Perhaps best known here for the nerve-racking "Audition", he has also made a number of truly weird and outrageous films like "The Happiness of the Katakuris", "Ichi the Killer", and "Gozu".  He is also something of a specialist in Yakuza films and this two and a half hour effort is one of his best, if you can take the relatively slow pace and escalating violence.  The plot concerns the tit-for-tat warfare amongst rival gangs, as the killing of a gang boss unleashes a crescendo of  revenge and counter-revenge.  Seen largely through the eyes of a junior thug whose mentor is eventually murdered, the film examines the concepts of honour (however misbegotten) and duty, wherever these may take one.  While I probably do prefer the director's more OTT offerings, films like this one prove that he is a master of his craft.