Vengeance Is Mine : 1979

Some people are born just like that – It is in their nature to kill.  

Maybe Japanese have a fascination with death.

Anyways, no Hara-kiri or Seppuku here : in ‘Vengeance is Mine’ {1979} by Shōhei Imamura, the protagonist is in a killing spree and it becomes obscure whether he or his victims should be termed an insect. 

He is shown to be a cold blooded serial killer devoid of any stimulation, inspiration, reason and remorse. No explanations are provided why he behaves the way he behaves. 

The film is based on a true story of a serial killer called Akira Nishiguchi, with tales of depravity, incest and conman ship flung all over.

The film does not make any moral judgment or explain any actions: you just witness the events.