Two guardians of the Nijo Castle, Shioya and Kamazawa, discover a map leading to a secret passage to Edo Castle. Instead of reporting their find to local authorities, they decide to blackmail the lords who created the forbidden passage. To prove their crime, Magistrate Toyama Kinshiro launches a private undercover investigation.
| Directing | Kinnosuke Fukada | Director |
| Writing | Shinji Kessoku | Writer |
| Writing | Tatsuro Jinde | Story |
| Camera | Sadaji Yoshida | Director of Photography |