This was the first book by Nicci French I read. I've read quite some other books by them afterwards, mainly because my aunt keeps getting them for me as Birthday/Christmas presents.
This is actually Nicci French's first book, and it centres on suppressed memories, and how much we should value the memories that are uncovered eventually.
It starts of slow and a great number of characters is introduced, but they don't get any depth. After that the story takes a lift and is more interesting. I'd already guessed the final plot twist, but do believe that these question about suppressed memories and certain psychological procedures are quite interesting.
Note: I read a Dutch translation of this book