A secret research organisation protects the world against existentially threatening “unknowns”, so that the public can continue their quotidian lives in blissful ignorance. Its Antimemetics Division specialises in anomalies that affect memory and perception; fighting and containing phenomena that cannot be directly recorded or observed. The story begins episodically, introducing a succession of mind-altering unknowns, but we soon perceive the shape of a larger Lovecraftian incursion below the surface, an...