It does make changes to the story, but compared to most adaptions, it actually retains some of the most important parts.

To minimize spoilers, I'll refer to the book character names.

I was happy to see the Morrel's part in the story retained, and that Haydee was back in it, in her proper role. These are KEY characters for the lead's character arc. Nortier is actually portrayed as he is in the book, Benedetto's changes have some... squick, and if I have any reservations, its that some people get off easier than they 'should' in the story. That all said, it works surprisingly well in the modern setting - they

I'm not fluent at all in Japanese, so it was all subtitles for me, but it never interfered with my enjoyment.

Dean Fujioka really transforms Saimon Dan from a happy-go-lucky idealistic young man into the 4-D chess playing count magnificently - so much so that it truly felt like two different men.