Now this is not to say there is anything wrong with this novel, which has won the CWA Debut Dagger Award and the Luke Bitmead Novel Award (of which I'd never heard, but never mind that), and has a great many five-star reviews on Amazon and elsewhere. I'm just riding a probably rather pathetic hobby horse here -- it's just that I think it doesn't do a writer any favours if you compare her to someone who she doesn't really resemble. But Ruth Dugdall clearly has done fine anyway, and this, her first novel, has been followed by two more, equally successful.
On her website Ruth says "my books explore the darker areas of himan behavior and how long-held secrets can affect the present". Certainly that is a good description of what happens here. Rose Wilks, an unhappy and rather unattractive woman in her thirties, has served four years of a sentence for murdering a baby who died in a fire when she had been babysitting him. Ruth is up for parole, and being assessed by a young probabtion officer, Cate Austin, who is new to the job. The narrative shifts between Cate's story, present day, and Ruth's 'Black Book' in which she recounts her own past history and the events which have led up to her arrest and imprisonment. A sad story it is indeed, and of course, being the sort of novel this is, there's a twist on the last page which I wasn't expecting (though I was expecting something).
So, if this sounds like your sort of book, go for it!