A clandestine struggle against malevolent occult forces threatens the stability of the modern world. Gregory Sallust, a resourceful intelligence operative, finds himself drawn into a conflict that transcends conventional espionage. He must navigate a landscape where ancient, dark rituals intersect with the geopolitical tensions of the era. The narrative follows his efforts to dismantle a secret society intent on unleashing supernatural chaos, requiring him to balance logical deduction with the unpredictable nature of the occult. The story unfolds through a third-person perspective that emphasizes the tension between rational investigation and the encroaching unknown.

Readers often note the distinct blend of traditional thriller mechanics with Wheatley's signature interest in the occult. Discussion frequently centers on the effectiveness of the protagonist's pragmatic approach when confronted with irrational, supernatural phenomena. Critics highlight the author's ability to maintain a consistent sense of dread throughout the narrative. The pacing is generally described as methodical, allowing for the gradual buildup of tension before the climactic confrontation. Many readers appreciate the historical context provided, which anchors the more fantastical elements in a recognizable reality.