A book that is interchangeably about, building a new sewerage system, a cholera outbreak and a missing wife. It should not work but it does. The key is the gritty real depiction of London in 1849. Unusually it is not from the perspective of the Ton, but from a working Engineer who moves between the worlds of the working, middle and some upper classes. It reminded me of Daniel Defoe - A Journal of the Plague Year. With a mix of fiction and fact and discussions of what London was really like and the huge hygiene and disease issues. So while interesting, the real interest was in the last chapter and the rest of the book lacked a gripping plot of the last chapter. Others saw dark humour and descent into madness of the main character. I just saw someone confused and frustrated, with desperation only truly noticeable in the last 20 pages. I think if more of the book was similar to the last few pages I would have enjoyed this more. But it is easy and quick to get through considering the subject matter and time period it is based in. So it you enjoy a slow build and real interest in the 1849 London I think you will enjoy this. If you are more interested in the mystery probably not.