Second Book of Rook

When young librarian knight Rook Barkwater is taken captive and forced to work for Vox Verlix nominally the Most High Academe, but no more than a prisoner in reality he stumbles across a terrible truth. Vox is brewing a plot to destroy the goblins and the shrykes at a stroke, so that he can seize control of the Edgeworld for himself.Can Rook foil Vox's plan and save the lives of his librarian friends and colleagues?