I saw the film adaptation of this long before I even knew it was based on a book. And it turns out that the film was based only on the first third of the book. That was probably a good idea as it gave them a chance to do it properly witout skimming over too much. It was probably the best part of the book too.
The stories are well written/translated and the excitement and tension is generally well maintained throughout despite being slowed down a little whilst the protagonist Anton wrestles with a variety of moral dilemas. While he works for the good guys, he finds out that they often have to be quite manipulative and ruthless in the pursuit of their ends. There's no room for a simplistic view of right and wrong here, more often than not there being many shades of grey in between.
There's always a bit of a twist at the end of each part although I couldn't help being a little disappointed by the way each ended, even though it was a lot of fun getting there. I'm quite looking forward to the next in the series.