In the early hours of April 13th, a five year old hemophiliac child was kidnapped by someone from Tanemura General Hospital in Tokyo, Setagaya. Tokyo Metropolitan Police Department Inspector Kitahara, who received the report, goes quickly to the Tanemura home, along with other police to speak to the family of the child. Then, suddenly, the phone rings. The kidnapper wants money.

The clerk of a trading company happens to have a large sum of money from his company in his possession. His girlfriend pressures him into fleeing with the money...

インチキ投資グループの会長・卜部(根上淳)宅に、一家皆殺しを予告する脅迫状が舞い込んだ。卜部の三女・土岐子(大場久美子)は警察に相談するも、ろくに取り合ってくれない。そばで聞いていたルポライターの研三(大和田獏)は興味を抱き、神津恭介(近藤正臣)に調査を依頼。ところが翌日の夜、長女の澄子(八神康子)は刺殺体で発見され、さらに数日後、今度は次女の烈子(増田葉子)が炎に包まれて殺害されてしまう・・・。

When an artist dies, the official cause of death is judged to be a stroke, but his daughter suspects foul play. She recruits the services of an assassin, who by chance encounters an old friend...

A group of seemingly ordinary merchants is really a band of assassins for hire. When they discover that all the assassins in Edo are being killed they must act quickly to find the culprit.