Washington, District of Crime. 1936.

Torsten Somersby is a private investigator with a deep knowledge of the occult and a dubious reputation because of the strange cases his expertise attracts. When a winged creature begins stalking the city, Torsten and his partner Nigel Clemmons are engaged by Christian Heurich, the immigrant brewmaster who employs more of Washington than anyone but the federal government. Torsten and Nigel follow the creature's trail from Heurich's brewery in Foggy Bottom to an old wrong committed an ocean away in 1861, and come to suspect the thing on the wing is less a monster than a soul long denied justice. They must navigate a dangerous landscape to uncover the truth behind "the fallen," before the past collects what it is owed.