Based on the 300-million Yen Robbery Incident.

Ryo Kamon, a man with a mysterious beauty and a past, was spending his free days while staying at a snack managed by his close friend Shuji Nonomura. Detective Iroku Shirado suspects Ryo of being the culprit in the robbery of 300 million yen and continues to nag him... Based on the great Showa era case of 300 million yen robbery.