Sequel to Shadowmarch. Southmarch is under siege by the fairy army and the teenaged regent, Briony, has been deposed by an ambitious noble. Briony is on the run, fleeing for her life. Her twin, Barrick, is lost, mentally and physically, behind the fairy lines. Far to the south, Qinnitan has successfully fled from the autarch, but now the autarch is besieging the city of Hierosol where she is hiding.
The second book in a trilogy often suffers from Middle Book Syndrome: the first book establishes the characters and the plot, the final book resolves everything, but the middle book has to somehow keep things going, and the author’s energy often flags. Williams moves the plot along nicely, from one cliffhanger to the next, and we see the main protagonists mature as they are tested.