Vienna, 1914. Lucius is a twenty-two-year-old medical student when World War I explodes across Europe. Enraptured by romantic tales of battlefield surgery, he enlists, expecting a position at a well-organized field hospital. But when he arrives, at a commandeered church tucked away high in a remote valley of the Carpathian Mountains, he finds a freezing outpost ravaged by typhus. The other doctors have fled, and only a single, mysterious nurse named Sister Margarete remains.