In the early 18th century, architect Nicholas Dyer is progressing work on several churches in London's East End. He is, however, involved in Satanic practices (something inculcated in him as an orphan), a fact which he must keep secret from all his associates, including his supervisor Sir Christopher Wren. This is all the more challenging since he indulges in human sacrifice as part of the construction of the buildings. Dyer's simmering contempt for Wren is brought closest to the surface in discussions they have concerning rationalism versus Dyer's own carefully disguised brand of mysticism.
In the 20th century, DCS Nicholas Hawksmoor is called in to investigate a bizarre series of murders by strangulation that have occurred in and around the churches designed by Dyer. The murders are all the more mystifying since the murderer appeared to have left no identifying traces, not even fingerprints on the victims' necks.
However the area is stalked by mysterious shadows, and it becomes clear that not only the weight of the investigation, but unseen forces from the past come to bear on Hawksmoor in a powerful, destructive manner.