John Rawlings, London's most colourful apothecary and occasional sleuth, is relaxing at the popular swimming baths, the Peerless Pool, when his peace is shattered by the alarming discovery of a drowned woman. The victim is identified as Hannah Rankin, as assistant at the nearby St Luke's asylum for the insane.
Assigned to the case by John Fielding, London's famous blind magistrate, Rawlings doesn't realise that he's scratching the surface of something far more complex than an isolated murder.
At St Luke's, Rawlings discovers a vital clue to Hannah's hidden past which leads to a strange case concerning a child's mysterious disappearance. Was Hannah involved? And why do his investigations lead him again and again to a house of sinister secrets in Bath?
