The Penhaligons are tracking the coven as they wreak havoc abroad-creating new vaewolves, attracting wraiths, building an army. Violet knows this: an attack will come when the river rises. What she doesn't know is why. The tree tapestry Mara spent a century seeking is the key, but the Penhaligons are running out of time to discover what it unlocks. When the coven returns to England, bigger and stronger than ever, it's not long before allegiances are tested, throwing Violet's tentative relationship with her sister into doubt. When the river rises, Violet must fight for her life, but in the midst of battle, sacrifices will always be made, and her best friend will be changed forever. Hell is here, and she brought friends.