Professor Manabu Yukawa (aka “Detective Galileo”): Professor of physics and occasional unofficial consultant to the Tokyo Metropolitan Police Department
Director Mamiya: Head of the Homicide Division
Detective Chief Inspector Kusanagi: Leads the investigation, college friend of Professor Yukawa
Detective Inspector Kishitani: Part of Kusanagi’s team
Detective Sergeant Kaoru Utsumi: Part of Kusanagi’s team and a friend of Professor Yukawa
Detective Inspector Muto: Detective, Kikuno precinct
Yutaro Namiki: Co-owner of Namiki-ya restaurant, father of Saori Namiki
Machiko Namiki: Co-owner of Namiki-ya, mother of Saori Namiki
Natsumi Namiki: Younger daughter of Yutaro and Machiko, sister of Saori
Saori Namiki: Eldest daughter of Yutaro and Machiko
Naoki Niikura: Music impresario
Rumi Niikura: Wife of Naoki
Shusaku Tojima: Owner of local food-processing company. Childhood friend of Yutaro Namiki
Maya Miyazawa: Owner of local bookstore and head of the Kikuno parade team
Tomoya Takagaki: Boyfriend of Saori Namiki
Eiji Masumura: Former coworker and roommate of Kanichi Hasunuma
Yuna Motohashi: Twelve-year-old girl, believed to have been murdered by Kanichi Hasunuma twenty-three years ago
Kanichi Hasunuma: Suspected murderer, never convicted