It is a terrific movie.
The director made a second film "Kuroneko" which is more overtly supernatural than "Onibaba." I would like to see that one some day.
They are both great, though I still slightly favor Onibaba. I mean just the thunderous theme song alone is a pleasure to listen to. Kuroneko has the strongest visuals and the creepier FX work, I'll give it that.