Edinburgh, 1849. Hordes pacientov, ktorí idú všetky cez mesto, s lekármi finding ich remedies powerless. And whispering campaign seeks to paint Dr James Simpson, pioneer medical chloroform, as a murderer. Determinovaný k vymazaniu Simpson's name, jeho protege Will Raven a former housemaid Sarah Fisher must plunge do Edinburgh's deadliest ulice a vychádza z toho, čo sa behom deaths. Soon tieto discovery, ktoré prinesú deaths evaded detection purely because it is so unthinkable.