Armed with secret knowledge, Juliette, now mayor of Silo 18 and her crew set out to rescue a world she hates but now understands better -- the world of the Silos with its rigid rules and terrible consequences for disobedience.

"In the underground city of Caverna, the world's most skilled craftspeople toil in the darkness to create delicacies beyond compare-- wines that remove memories, cheeses that make you hallucinate, and perfumes that convince you to trust the wearer, even as he slits your throat. On the surface, the people of Caverna seem ordinary, except for one thing: their faces are as blank as untouched snow. Expressions must be learned, and only the famous Facesmiths...

When Will Burrows and his friend Chester embark on a quest to find Will's archaeologist father, who has inexplicably disappeared, they are led to a labyrinthine world underneath London, full of sinister inhabitants with evil intentions toward "Topsoilers" like Will and his father.

Eleven-year-old Gregor returns to the world beneath New York City to rescue his kidnapped sister, Boots, and fulfill a prophecy that will restore peace to the people, bats, rats, cockroaches, and spiders who populate the underworld.

Thirteen-year-old Sully Stringfellow, his arch-nemesis Izzy Cisco, friend Moleman, and a league of long-forgotten plumber heroes team up to save Nitro City from mutant creatures in the sewers.

In a ruined and toxic landscape, a community exists in a giant silo underground, hundreds of stories deep. In a society full of regulations meant to protect the community, Sheriff Holston, unexpectedly breaks the greatest taboo of all: he asks to go outside. An unlikely candidate is appointed to replace him: Juliette, a mechanic with no training in law, whose special knack is fixing machines. Now Juliette is about to be entrusted with fixing her silo,...

"Anzu has just moved to a new town during Obon, a time for families to remember and celebrate their ancestors. Ever since her obaachan died, though, Obon has lost its magic. She doesn't feel much like celebrating anymore. While avoiding holiday festivities, Anzu spots a stray dog down the street. A dog that seems to be staring right at her. But when she chases after it, she slips and falls down a ridge, losing consciousness. When she awakes, she's...