After the events of Corpse Party: Blood Covered, the survivors try coming to terms with the traumatic incident that took place in Tenjin Elementary School. Though the curse was broken, they lost many friends, who have subsequently been forgotten by everyone else; anyone who perished in the hellish dimension has been erased from existence.

However, not everyone was forgotten, and it is this small ray of hope that leads two of the survivors to investigate the culprit's home and discover the origin of the curse. Here, they find the infamous Book of Shadows, an evil tome containing many dark curses, and surprisingly, even a spell for resurrecting the dead. With no other option, they perform the ritual, but end up with far more than they bargained for.

Corpse Party: Book of Shadows follows these two survivors as they tempt fate once again, while also providing a look at the intertwining stories of other characters from the series.