I think I've just discovered a little bit of a drawback to ebooks - no blurb on the back to repeat here :)
But Blood Atonement is a followup to the first Nigel Barnes book, The Blood Detective, which I really enjoyed. The idea that the past - the genealogy connection - directly impacts the now isn't a new idea, but it's well explored in these books.
The candle on the ledge guttered as it neared its end, shadows dancing on the wall. Beside her Sarah sensed the rhythmic rise and fall of her sisters' chests. Henrietta's and Emma's ability to fall asleep as soon as their heads lay on the pillow infuriated her, while she tossed and turned seeking sleep that took an age to arrive.
Someone killed Katie Drake, a single mother living in Queen's Park, and abducted her 14-year-old daughter. Detective Grant Foster sees chilling parallels with the disappearance of a teenager 3 years earlier. He calls on genealogist Nigel to piece together the links between the families of the two girls. The trail leads Nigel back to 1890.