The Samurai (1962)

The Water Castle (6x8)

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Having killed Tanba, Saizō reports to Tonbei that he will find out the true colours of the remaining four Fūma. But Oboro overhears his conversation. Knowing the truth, Kotarō uses Saizō to send out an invitation to Shintarō and Tonbei to come to a nearby waterfall, then sends out Oboro. Shintarō defeats Oboro and she runs away. Tonbei discovers a cave behind the waterfall. This is the Water Castle. There they find the last map, for the Fire Tower, but Kotarō, who has killed Saizō, steals half the map and runs off with it.