Summary

Clockwork Angel opens with a Prologue set in London, in April of 1878. Will Herondale and his parabatai, Jem Carstairs, are fighting a demon in an alleyway. Will kills the demon, and Jem finds the body of a young girl. Jem says he believes the demon did not kill the girl. Will says he will investigate, and the two boys talk briefly about the fact that it will mean traveling in places typically inhabited by Downworlders. They find a knife with an odd symbol of two snakes swallowing each other. The bodies of the snakes form a circle.

A month later, Tessa Gray arrives in Southampton. She always wears her mother's necklace that features a clockwork angel, ticking away even though there is no apparent way to wind it. Tessa had lived in America with her aunt, who recently died. Tessa had to...