Changeling

Ivy has learned to live with friends that ordinary people cannot see, ever since she found out that her former flatmate Demi is a runaway fairy king. She holds down a regular job, lives in a normal flat in Dublin, and tries to keep her life as free of weirdness as she can. That mostly means avoiding any thought of the Enemy, its coming visit, or the fact that Demi has less than a year left to live.

Then a woman dressed like the Enemy turns up in Ivy's flat seven months ahead of schedule. Ivy sees a chance to end the Enemy's deadly visits for good, but the woman burns to death in the street. It appears that a three-hundred-year-old serial killer is changing its methods.

Strangers are also arriving in Dublin, looking for the source of a catastrophe that could change the world, and it is somehow tied to both Ivy and the Enemy. As Ivy digs into the origins of past murders and disasters still to come, it becomes clear that she may be the Enemy's next target.