If you haven't seen the first chapter (read my review here), then don't see it, you won't understand a thing. For the other, don't expect as much a punch in the face as the first one, and you'll be very happy to have seen it. I'll say the mellowing out is logical and is perfectly well done and well adapted to the story. Enjoy!
Ewan McGregor and Robert Carlyle.
Synopsis & information: http://www.imdb.com/title/tt2763304/
