The Mysterious Cape(1963)

Ryujin Misaki, located at the edge of the Genkai Sea, is known as an isolation ward for leprosy patients. When Saotome, a sword master and guard of the Shogun, hears news of a doctor gone missing, he begins to suspect that things are not what they seem at Ryujin Misaki. Intent on discovering the truth, Saotome launches a private investigation.