The story is about an "eminent personality" (快傑, kaiketsu) with a black hood (黒頭巾, kuro zukin) in 1868, the first year of Boshin-War. The "Black Hood" independently enforces law and order against predatory criminals in nighttime Edo. However, this tale mainly describes the efforts of Sakakibara Genichiro to prevent a battle for Edo. Samurai of Satsuma and Choshu want to conquer the capital of the Shogunate to depose the Shogun and reinstate the Tenno as sole ruler.
There are numerous films and TV series on this topic (kaiketsu kurozukin), at least twenty according to Japanese Wikipedia. The TV series described here was broadcast in 1981.
The protagonist in the film, Wakayama Tomisaburo, plays three roles: 1. The mysterious "Black Hood", a "Zorro" from 1868 - 2. Sakakibara Genichiro, the real person behind it and who also negotiates with the warmongers - 3. Incidentally also the fortune teller (face reader) Tenmeido.