Cordelia Carstairs is a Shadowhunter, she has been fighting demons since childhood. When her father is accused of a terrible crime, Cordelia and her brother travel to London in the hope of averting the catastrophe that threatens their family. Soon Cordelia meets James and Lucy Herondale and with them plunges into the world of glittering ballrooms, secret dates, and meets vampires and sorcerers. And hides her feelings for James. However, Cordelia's new life is shattered when a series of horrific demon attacks across London occur. These monsters are unlike the ones Shadowhunters have fought before - they are not afraid of daylight and seem impossible to kill. London is being quarantined...