Egypt, 1914. The outbreak of war in Europe casts ripples even in Cairo. Gareth Owen, Mamur Zapt and Head of the Khedive's Secret Police, is given the task of rounding up enemy aliens. But determining who counts as a German proves contentious.

And then there's the face in the cemetery. Who disturbed the mummified remains of cats by placing a human corpse among them? Is the villagers' talk of a mysterious Cat Woman mere superstitious nonsense, or something rather sinister?

Owen has more pressing concerns in the shape of missing rifles and dubious gun-toting ghaffirs or watchmen. But the face in the cemetery refuses to go away, and Owen comes to realize that it poses questions that are not just professional but uncomfortably personal.