Arlo and her friends struggle to rally against an overwhelming foe before time runs out in this gripping final book in the Hollow Star Saga, the urban fantasy series about fae in Toronto that's The Cruel Prince meets City of Bones! Arlo Jarsdel has lost everything. Her family. Her freedom. Her name. And now that she's sharing her body with Ruin, the formidable titan of devastation, she's even beginning to lose herself. In their most dangerous game of deception yet, Arlo has just one goal: destroy the three Bone Crowns corrupting the mortal and immortal realms before her time runs out and Ruin takes permanent control of her being. With Celadon fighting on the political front against the ruthless High Queen Riadne--now armed with the cataclysmic power of her Crown, the Sins, and Ruin--Vehan and Aurelian are scrambling in secret to build an army to rival Riadne's infernal forces. Meanwhile, Nausicaä will do whatever it takes to save her girlfriend from obliteration, despite knowing the odds of survival are nearly nonexistent. When the line between hero and villain becomes blurred, and bonds are put to the ultimate test, it has never been more imperative--or more difficult--to stand united. For this is not the first lifetime that these five friends have faced the evil behind this impending war, but if they can't find their way back to each other, it might just be their last.