Fourth in the generally excellent Slow Horses series (see here for reviews of 1-3), this is the weakest of the novels so far, primarily because it relies on too high a level of suspension of disbelief. But, if you can get over that, you will be rewarded with being able to enjoy the author’s wonderful cocktail of strong characters, snappy dialogues, and plain good writing.
This book begins with a terrorist atrocity in Britain. At the same time, current spook River Cartwright’s grandfather – an old spook – is rapidly descending into the hell of dementia. The author does an amazing job – assuming you buy the central idea – of tying these threads together.
There are turns, twists, surprises, and pathos aplenty.
In short, if you have not read these books, start at the beginning. And do it now!