【山口組を命懸けで守ったにもかかわらず、最後は組長に裏切られた男。】高山清司と司忍を「クズ」と呼び、「お前たちは必ず後悔する」と言い放った一人の男――。

The Yamaguchi-gumi of the Showa era— There were yakuza who truly believed they would "sacrifice their lives for their boss." Kenji Nishiriki, one of the three pillars of the Yamaken-gumi. He acted in retaliation for the attack on Kazuo Taoka, the "Bellamy Incident," and in the interrogation room, he bit off his own tongue to protect his boss. Sixteen years in prison. And after his release, what he saw was— a Yamaguchi-gumi that had been "completely changed," dominated by money and power. Yoshinori Watanabe. Shinobu Tsukasa. Kiyoshi Takayama. Why did the chivalrous spirit of yesteryear disappear? The last militant man of the Showa era speaks about the dark side of the Yamaguchi-gumi. "Farewell, Boss, My Beloved Yamaguchi-gumi"— What is the true meaning behind those words? This is the story of a man who witnessed the death of the yakuza spirit.