This
remarkable and acclaimed debut novel, by the Newbery-winning author of When You Reach Me and the new
instant classic The List of Things That Will Not
Change, introduces readers to a captivating,
hidden world below the ice.

Peter is thrilled to join his parents on an expedition to Greenland. But
when they finally reach the ice cap, he struggles to understand a series of
frightening yet enticing visions.

Thea has never seen the sun. Her extraordinary people, suspected of
witchcraft and nearly driven to extinction, have retreated to a secret world
they’ve built deep inside the arctic ice.

As Thea dreams of a path to Earth’s surface, Peter’s search for answers brings
him ever closer to her hidden home in this dazzling tale of mystery, science,
and adventure at the top of the world.

A mystic thriller. -Entertainment Weekly

Optimistic science fiction that highlights human ingenuity and survival
under dire conditions. -The Wall Street Journal