This film was introduced in a number of international film festivals and I saw it during one of them and glad I did. It started slowly with main character Tanaka, journalist, (Satoshi Tsumabuki) carrying the story line forward by interviewing different people involved in a murder case. It's easy to miss some plot lines as a lot of characters were introduced one by one, especially with the names and flashbacks. I think that's the film's direction as it leaves the viewers to connect the dots on their own progressively, dropping hints here and there. As others have suggested, recommended to watch second time as some of the earlier scenes will make sense. I myself came out from the cinema questioning myself why and how, trying to make sense some of the plots. It is one of the best crimes, thriller movies worth the watch for those who enjoy the genre.
Both Satoshi and Hikari Mitsushima (female lead) threw in some of the best performances. I am well familiar with those two and quite enjoyed some of their previous films. They played some of the difficult scenes really well.
Please give it a watch, anyone who don't mind the slow pace and story gradually unravelling up to the final climax. For reference, this film is first feature length film from director Kei Ishikawa who studied film directing in Poland on government scholarship.