Detective Umon’s services are called upon when ronin Yaichiro is killed with a peculiar weapon, a stone wrapped in a towel.

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Main Cast: Ryutaro Otomo, Kotaro Satomi, Eitarō Shindō, Satomi Oka, Hiroko Sakuramachi, Kikuko Hojo, Kyoko Aoyama, Mikijiro Hira, Ikkō Ōkuni, Shinnosuke Ogata

Director: Eiichi Kudo

Writer: Hyōgo Suzuki

Editor: Shintarō Miyamoto

Cinematographer: Sadaji Yoshida

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