The "Books' Curse"--an ancient hex that activates when a book is stolen from the massive library, Mikura Hall, turning the entire town into the setting of a story. To break this curse, high schooler Mifuyu is tasked with journeying through these story worlds to track down the thief. This time, she'll be navigating the dangerous streets of a hard-boiled noir novel, as well as a fantasy adventure surrounding the large and mysterious "Silver Beast"!! And will the book thief reveal themselves at last?!