The dark side of the soul is a terrifying place.

"I'm about to be murdered!"

With this message, an intruder wakes up Lizeth Frontenac in the middle of the night. He gives her his name, his address, and begs for her help, then vanishes into thin air before she can do anything.

Lizeth doubts her own eyes. Was the man just a dream? A hallucination? In the morning she learns he was neither, for a body is found a state away, in the same town, on the same road.

And he wasn't the only one. On the same night, under the same full moon, all across the country, eleven other people are also killed.

When a victim's distraught boyfriend seeks out Lizeth and her sister Hyla for help, they are plunged into a mystery so intricate, tracking murders so perplexing and numerous as to boggle the mind. Is it a ritual? A cult? One killer or a dozen? The answer keeps slipping through their fingers.

And one of their own might be next.