How many movies have Osamu Tanaka and Shōzō Fukuyama collaborated on?

They have worked on 4 movies together! Their first movie together was Japan's Violent Gangs: The Boss and the Killers (1969) while their highest rated movie together was The Armed Organization (1971). They have not worked together since A Flower in a Neon Jungle (1973). They are most known for their drama films together.