Despite Clover’s victory over the Seamstress, war continues to rage between the fledgling United States and Napoleon Bonaparte. Clover and Nessa join the Women’s Service League expecting to dole out soup and socks to invalids and orphans.

Instead they’re tasked with rooting out the last of the pestilential Vermin—vicious creatures animated by magic, which have been terrorizing the countryside. But when the group is attacked by a new kind of monster—a sharp-toothed harehound with bloodshot eyes—they discover a much greater threat: the grotesque Underking and his army of twisted creatures. With the help of a Paper-Doll Witch, an elegantly dressed skeleton and Susanna the bad-tempered Doll, Clover and Nessa must defeat the Underking before he conquers the whole land.