Toronto, July 1895. It comes as no surprise to Detective William Murdoch when Dolly Merishaw, midwife and abortionist, is murdered. Although she wisely kept quiet about her clients, her contempt and greed often left them resentful and angry. But when a young boy is found dead in Dolly's squalid kitchen a week later, the detective isn't sure if he's hunting one murderer — or two.