This film tells the story of a journalist in a monthly magazine in Japan. He revisits a story of the gruesome murder of a seemingly perfect family when it is close to the one year anniversary of the murder. He interviews the people who knew the victims, discovering uncomfortable truths of the individuals involved.
"Gukoroku - Traces of Sin" is a slow moving film. The interviews are slow and dialog intense. These interviews and flashbacks reveal the true nature of the victims when they were alive. To be honest, the interviews are not that thrilling or engaging. It gets rather boring towards the middle. However, the last section of the film gradually descends into a exciting and gripping story. The ending seems to be an open ending, insinuating a horrible deed, unless I missed an important clue in the film.
Overall, I think the ending takes a bit too long to build up. It is a good ending, but I have lost interest before the ending to care about it.