"Adam Roberts has got what it takes."--Peter F. Hamilton

Tighe lives on a wall that towers above his village and falls away below it. Though vast and unforgiving, the Worldwall is all he and his people know, and they cling on for dear life. Until one day, Tighe falls--and falls, and falls...and survives. He finds a new part of the wall, a vast expanse of cluttered ledges packed with more people then he ever imagined existed. More than that, he encounters war, fought by the Popes and their armies. A war he must join, and that will take him on a journey into the heart of the mystery behind the wall. Endlessly imaginative, this novel by the acclaimed author of Salt presents a radically different universe than any you've read about before.