In a secret world where half-angel warriors called Shadowhunters are sworn to fight demons, parabatai is a sacred word. A parabatai is your best friend and battle partner. Parabatai can be everything to each other--but they can never fall in love. Emma Carstairs ia a Shadowhunter, the best in her generation. Together with her parabatai, Julian Blackthorn, she patrols the streets of Loa Angeles, where faeries--the most powerful of supranatural creatures--teeter on the edge of open war with Shadowhunters. When bodies--both faerie and human-turn up, bearing marks that match those found on Emma's own murdered parents, an uneasy alliance is formed. This is Emma's chance for revenge--and Julian's chance to get back to his brother, a prisoner of the faerie Courts. All they have to do is solve the murders within two weeks... and before the murderer target them.