A long-dormant volcano explodes, blacking out the sun, mowing down trees, and filling the land with soot and ash. The Lord of the Locusts is released with the eruption. Against this apocalyptic backdrop, the Bone cousins along with Thorn and Gran'ma Ben struggle to reach safe haven in the city of Atheia. Meanwhile, Lucius Downs lies severely wounded and trapped with the villagers in the camp at Old Man's Cave.