I am a little torn about this book. I loved the setting, the way the author (in fact two authors - husband and wife) described London, especially the parts you would never see as a tourist. The first chapter, telling about an abduction of a little girl more than twenty years ago was quite catching. Then the author starts to introduce the main characters - and there are many of them, so the book gets a little slow. Some of the events seem to be almost unrelated and the main character, Frieda Klein, a psychologist with personal problems, is not entirely believable all the time - and I have problems accepting that a layperson - okay, a psychologist in this case, which partly explains it - helping the police solves the case much faster and better than the police.
On the other hand, the characters were well drawn, the case was interesting - although I had some problems with the twin issue. I know that there seems to be a bond between identical twins, even when they are not raised together and that their lifes tend to have a lot of similarities - but some of the stuff in this novel was hard to believe.
I liked the book and will read the sequels - in fact I already read the second book of the series before the first (not a great idea in this case - too many spoilers).