Mitsuhiko Tsuburaya provides a large collection of manga to Conan Edogawa, who continues reading despite being overwhelmed by its size. Meanwhile, Kogorou Mouri is tasked with safeguarding the family's treasured sword in their dojo, as per Kaitou Kid's plan to steal it. Upon reaching the dojo, Conan and his companions encounter Yaiba Kurogane, who joins them in an attempt to prevent the phantom thieves from executing their scheme. However, while investigating the case, Conan discovers something unusual.