Ada is gone, taken by a group of magic-resistant warriors with a grudge against the Alliance. Kay is stranded on Earth, with no way to reach her.

But he won’t accept that Ada is lost.

Ada refuses to resign herself to her fate as a weapon of the Stoneskins. Tapping into her own magic might be her key to escape, but now she’s in an unknown world, far beyond the reach of the Alliance. And the terrifying StoneKing has his eye on her -- and her magic -- for reasons she never could have seen coming.

Kay puts his job, and his life, on the line to get to Ada. But with powers shifting inside and outside the Alliance and an old enemy waiting in the shadows, the countdown to war has begun… and Ada is right at the centre.

This blend of contemporary fantasy, murder mystery, and an action-packed world-hopping adventure will appeal to fans of the alternate Londons of Ben Aaranovitch and VE Schwab, the modern magic of the Dresden Files, and the genre-blending of Genevieve Cogman’s Invisible Library series and Diana Wynne Jones’s adult novels.