Baghdad, the capital of the world, is a city crowded with stories, and founded on secrets. But some secrets, and some stories, can be deadly...Ismail al-Rawiya is a thief who dreams of being a poet. He is drawn to Baghdad, and to the court of the Khalifah Harun al-Rashid, where fabulous wealth can be attained by those who survive the rivalries, the politics and the whims of the capricious monarch. In the turbulent city, Ismail falls into the company of the poet Abu Nuwas, known as the Father of Locks. Abu Nuwas is a brilliant artist, but also a decadent drunkard with a taste for trouble.
The Father of Locks has his own secret: he is an irregular and reluctant agent of the scheming Wazir, Ja'far al-Barmaki, who now assigns him to investigate reports that the Devil is stalking the streets of Baghdad. Together the poet and the thief uncover a hidden world, of forbidden cults, foreign spies, and a mysterious Brass Bottle. When children start to disappear, it seems that there must be substance to the dark rumours of evil spirits and human sacrifice that haunt the city. But the truth that Ismail and the Father of Locks uncover is more shocking still.