I just received this set a few days ago and finished all 4 episodes. I was not disappointed by any of the scripts. And, since I have not read all of Val McDermid's books I cannot compare the series to her books. What I can say is for me, the scripts are gripping, well, written, and quite thought provoking.
As for the acting, Robson Green, as always, is superb and Simone Lahbib is wonderful! I have followed her career in Bad Girls, Monarch and Heartless and was impressed with how she has handled the transition to WITB. The relationship between her character Alex and Tony is quite different than that between Carol and Tony and had me on edge until I got comfortable with it. And let me not forget the great supporting cast!
I have already watched a couple of episodes twice because they are filled with so much and I find I can always pick up something I missed in the first viewing. I was captivated by many of the themes, Tony's ability to get into the criminal's mind and in one episode the symbolic imagery used. This episode did have some graphic scenes in it, but as always, Tony was able to find the hidden meaning in it all.
I was thinking of giving this a rating of 4 only because I was a bit disappointed in the DVD set for two reasons: 1) There are no scene selections or chapters. So, if you wish to watch a scene over you must rewind the whole scene, you cannot go to previous.
2) There is no captioning for the hearing impaired (I have a friend who is hard of hearing and will definitely let her know this so she isn't disappointed if she purchases the DVD set).
But, I love the show so much I did not wish to give any indication I was displeased with the show itself. For any fan of WITB you will not be disappointed in the material at all!