High school student Yoshiro Kobayashi (Mahiro Takasugi) is the great-grandchild of the first president of the Boy Detectives Club. He enjoys time with his friends Watari (Gaku Sano) and Saya (Mayu Hotta). One day, the Fiend with Twenty Faces appears in front of Yoshiro. Mysterious cases then takes place in sequence.
高杉真宙
as Yoshihiro Kobayashi / Yoshirou
堀田真由
as Akechi Saya
佐野岳
as Watari
長村航希
as Kaito Kurosaki
板垣瑞生
as Shotaro Yumeno
前田旺志郎
as Atsushi Tsukahara
神谷浩史
as The Fiend with Twenty Faces of the Phantom (voice)
佐藤二朗
as Manaka [Teacher]
丸山智己
as Yoshinobu Kobayashi
Higashino Mizuki
as Saotome [Teacher]
Koki Ishige
as Kobayashi Yoshiro [Young]
押田岳
as
