けんか空手 極真無頼拳 (1975)

Masutatsu Oyama is recruited by his former Army friend to work for a crew of gangsters, but when they kill both his girlfriend and his best friend, Oyama flees away to a small town where he both learns lessons in martial arts philosophy from a wandering master and helps a young boy take on a challenge to fight a ferocious captured bear to win money for the boy's injured father.