After her father is murdered, Komugi Yamashita finds a letter naming a suspect as innocent. The suspect is the son of a criminal executed 22 years ago. Seeking help from lawyer, she uncovers shocking truths about her father's past.

A community is shocked when the bodies of an elderly man and the manager of a home-visit nursing centre are found. The passing of 42 elderly patients is connected to Shiba, a caretaker recognised for his affection and dedication.