The fourth book in a gripping young fantasy series from the
author of THE HUNGER GAMES, with a striking newly-designed cover.It's
only been a few months since Gregor and Boots returned
from the Underland, leaving their mother behind to heal from
the plague.

Though Gregor's family receives frequent updates
on her condition, they all know Gregor must return to fulfil
his role as the warrior who is key to the Underlanders' survival.

Accompanied by his now-talkative little sister Boots, still considered
the honorary "princess," Gregor joins forces with another princess
- 12-year-old Luxa - and Ripred the rat to defend the Underlanders
and the vulnerable "Nibblers," or mice, from the rat army.