How to Forget Sadness: Documentary of Nogizaka46 Released 2015-07-10 is a story that falls under the Documentary category. Movie Story "A documentary about Japanese idol group Nogizaka46. "A method to forget sadness" will show how the Nogizaka46's members were, how they really felt, and how they strived while facing the cruel world of showbiz. How were their lives off the screen? Well, find out by yourself.".