Depending on if you like Japanese action films, there's two sets of films I would recommend and probably suggest worth immersing oneself into; the "Zatōichi" film series (I would actually include the Rutger Hauer "Blind Fury" incarnation/ homage) from mid 60s to 2003, of which I'm missing 3 films and "Kozure Ōkami"("Lone Wolf and Cub") from '72 - '80, of which I'm missing 1 film.