"Hawksmoor" is a novel that alternates between the 18th century and the 1980s, focusing on two characters both named Nicholas Dyer and Nicholas Hawksmoor. Dyer, an architect in the 18th century, constructs seven churches in London, each with a dark and sinister secret. In the 1980s, Hawksmoor, a detective, investigates a series of murders that occur in the same churches. The narrative explores themes of history, time, architecture, and supernatural elements, creating an eerie and atmospheric tale.

In a unique blend of noir detective fiction and speculative fantasy, the book explores the coexistence of two distinct cities occupying the same geographical space, yet remaining invisible to each other due to a strict set of societal rules and the mysterious force of "Breach" that enforces them. When a young woman is found murdered, a seasoned inspector must navigate the complex and often perilous overlap of these two cities to solve the crime. His investigation challenges the rigid separation of the cities, uncovering a conspiracy that blurs the lines between the two and threatens the very fabric of their existence.

In this urban fantasy novel, a young London police constable discovers he has a unique talent for magic after encountering a ghostly crime witness. Recruited into a secretive unit that deals with supernatural threats, he finds himself navigating a world where magic is real, and the city's rich history comes alive in dangerous ways. As he learns to master his newfound abilities, he must solve a puzzling murder case that intertwines with dark magical forces, all while trying to maintain peace between the mundane and the magical realms that coexist within the vibrant and historic landscape of London.