Tell and Wren face a wraith?a sorcerer gone rogue?in this third and final book in the Children of the Black Glass middle grade fantasy series that's Howl's Moving Castle meets Christopher Paolini!

Wren, a captive in the evil sorcerer Desert's house, learns Desert has grown even more terrifying?she's melded herself into a human body to become a wraith. Yet, even though she now wields more power, more strength, and more magic than ever before, Desert's still not satisfied...not until she consumes Wren's too.

Tell, separated from his sister for the first time in his life, will stop at nothing to save Wren, and while he lacks magic himself, he discovers one of their friends has mystical sorcerer powers and is as determined as Tell is to save Wren?the girl who once saved him.

It will take quick wits, mountain training, and sorcerer allies old and new to vanquish Desert once and for all. Failure would mean losing the city of Halfway...and each other.