June 1815. When Henry Morton is called to the scene at Portman House in Claridge Square, the Bow Street constable finds a man dead in a hackney coach--ostensibly of asphyxiation. He was Halbert Glendinning, a gentleman of unsullied character. Then why was he seen frequenting one of London's most notorious dens of iniquity? And why has the driver of the coach vanished into the night? While Sir Nathaniel Conant, the chief magistrate at Number 4 Bow...