Detective Murdoch investigates when a wealthy family's pregnant maid is found dead in an area frequented by prostitutes.

Detective Murdoch refuses to believe the coroner's conclusion that his young friend and protégée, Constable Oliver Wicken, committed suicide. However, the only possible witness who could solve the mystery is locked away in a lunatic asylum.

Detective Murdoch investigates the murder of Dolly Capshaw, a mid-wife who, it turns out, was also an abortionist.