On a stormy night in 1813, a doctor is called to the aid of two prostitutes in childbirth. To one is born a healthy girl, Henriette, to the other, what can only be described as a monster: a boy, Hercules, deaf-mute and hideously deformed, and with the power to read minds.

As he tells the story of Hercules' bizarre and colourful life, which leads him from the bordello of his birth to a travelling freak show and then a Jesuit monastery and an asylum, Vallgren paints a magical picture of nineteenth-century Europe. This picaresque fable is filled with curiosities but is, at its heart, an extraordinary and unforgettable love story.