It's a story about loss and isolation that comes from not being able to accept that loss. Ryoichi has resorted to living in the mountains alone in his father's cabin. He doesn't believe in people becoming slaves to their employers, so he tries to disrupt and eventually end this system of oppression by killing the bosses who oppress by sending them bombs. But in my opinion, all of this isn't so much what Ryoichi wants but it's a way to get control over something meaningful while he mourns the loss of his family and is clearly wallowing all on his own, not even allowing his own sister , the only other living family, to touch him. And when she confronts him he acts coldly despite obviously loving her. Everything is going as Ryoichi plans when one day he gets visited by a ghost in the lone cabin who suddenly starts intervening in his life. But the ghost is here with a purpose. This is where we go deeper into our main characters psyche and see his descent into insanity. I thought this was a great film with a purpose. Definitely must watch.