Six months have passed since Lirael and Sameth fought off the Destroyer and saved Nicholas Sayre's life. Still recovering from his horrible ordeal, Nicholas is nonetheless eager to return to the Old Kingdom and his friends. But first he must endure a country house party organised by his powerful uncle, with the wealthy, eccentric Dorrance as the guest of honour. Nick hates the idea, especially since the people there don't believe in magic or necromancy. Even worse, they have a strange creature locked up in a display case.
Things take a truly horrific turn when Nick is kidnapped, and his Charter-infused blood is fed to the creature, which promptly goes on a rampage, drinking blood from anyone it encounters to build its strength. With the Abhorsen days away and no way to stop a savage, incredibly strong Free Magic monster, what can Nick do to stop Dorrance and 'the creature in the case'?