Shinobi no Mono 4: Siege - 1964 - 6/10
AKA - Shinobi no Mono Kirigakure Saizō // 忍びの者　霧隠才蔵

The narrative picks up 14 years after the last storyline.
New characters are introduced with actors from the previous trilogy (Raizô Ichikawa, Tomisaburô Wakayama).
(This has confused some viewers. This is perhaps not a series to binge through.)
Anyway, the Shogun has conquered all of Japan save for one holdout fortress.
Ninjas slither for both sides. For coin, for honor. Assassinations and intelligence gathering.
A romance is squeezed in with a fallen noblewoman, and all stops are pulled out for an explosive finish.