Isaac--a wolf-like clepsit from a human family--and Wren--a human living with a clepsit family--must band together when an army of vorcans rises from underground, intent on waging war.
- ISBN13 9780553510126
- Publish Date 19 September 2017
- Publish Status Remaindered
- Out of Print 11 August 2021
- Publish Country US
- Imprint Random House Books for Young Readers
- Format Hardcover
- Pages 320
- Language English