Istanbul, 1683: Mehmed IV, sultan of the Ottoman Empire, is preparing to lay siege to Vienna, capital of the Holy Roman Empire, when a naked man covered in tattoos arrives in his bedroom to deliver a world-changing message. Paris, 2017: Ottoman flags have been flying over the city for 300 years, ever since its fall, but Kamal Arslan Agha, an officer in the sultan's secret police, is starting to question his orders. Amid rumors of an impending war with the Christian Republic of America, Kamal is called in to investigate sightings of a tattooed man near the Seine. But what he discovers is a secret buried in the empire's past, a secret the Sultan will do anything to silence.

"Alternate histories don't get much better than this thought-provoking mind bender…. This ranks as a classic of the genre."—Publishers Weekly (starred review)