I picked this book up as I felt like a lightweight detective, seeing I was wanting to read something whilst a bit under the weather from the flu. It turned out that this book was much heavier than I had anticipated, but nevertheless extremely readable, and I certainly didn't regret it.
The characters were just brilliant, so complex and changing and engrossing. Especially the central character, Faith, is very interesting, and she is complicated by starting out as a child and ending up as an adult. So the book is a coming-of-age story, a detective and a psychological thriller, all in one.  It is also a  frame story, because we are told very early on 'whodunnit', and the plot is more about how it happened, and examines the question of how inevitable it was (or not).
As a further bonus, there were some nice nature descriptions. " The well... had very clean-looking weed like streaming hair growing in it.". That must be 'my' Ranunculus! Of course, "weed" is a pity.
I hadn't read any Ruth Rendell for years. Now I am wondering if they are all that good, or was this an exception.