Not at all what I was expecting given the marketing connotations of The Grudge and Ichi the Killer. Trepanation as an avenue for supernatural psychology. I didn't always understand it*, but overall I liked what I saw.
I guess the final note was about empathy. You don't need trepanation to see other people's problems. You just need to put your ego aside, and connection will follow.
This might be the first film I've seen from Avex. I'm familiar with their record label (e.g. Namie Amuro). At the very least it's the first time I've seen their logo so prominently displayed.
More notes later.
*the car/sand scene was kind of super confusing. I wasn't sure how he was actually helping...