If you loved Hara-Kiri: Death of a Samurai, try Shinsengumi: Assassins of Honor
A bridge between a film you've already seen and one most people haven't. Shinsengumi: Assassins of Honor has roughly 8.8× fewer votes than Hara-Kiri: Death of a Samurai — it's a deeper cut, not a mainstream recommendation. Here's what they share, and what the second one does that the first one doesn't.
What they share
Theysit in Drama / History territory. If that's the register that drew you to Hara-Kiri: Death of a Samurai, the second film will land in a comparable space — through a different lens.
What Shinsengumi: Assassins of Honor is
You're a Shinsengumi recruit in feudal Japan, loyal to a shogun slipping from power. But imperial loyalists plot his demise, testing your honor. Sawashima films in widescreen, with rapid cuts. What remains after the final sword clash is brotherhood.

