Detective Umon’s services are called upon when ronin Yaichiro is killed with a peculiar weapon, a stone wrapped in a towel.
| Directing | Eiichi Kudo | Director |
| Writing | Mitsuzō Sasaki | Original Story |
| Sound | Naotake Fujimoto | Sound Recordist |
| Camera | Sadaji Yoshida | Director of Photography |
| Lighting | Yoshiaki Masuda | Lighting Technician |
| Sound | Seiichi Suzuki | Original Music Composer |
| Writing | Hyōgo Suzuki | Screenplay |
| Art | Ryuji Tsukamoto | Art Direction |
| Editing | Shintarō Miyamoto | Editor |