There was this book called The Nanny Murders by Merry Jones

Excellent read, really captivating. It definately gets the wheels turning.
The plot was somewhat complex, there were several subplots (like four), so it took a lot of unexpected twists and turns. I liked the subtleties sprinkled throughout, details you'd remember reading, really couldn't appreciate how they could even be remotely related, but then Jones ties it all together. Good stuff.

I'm now reading Without Consent by Frances Fyfield...