In this epic fantasy from the acclaimed author of The Grey Bastards, a knight's valor is tested as he keeps a closely guarded secret from evil forces. Only the most resolute are chosen to join the ranks of the Knights of the Valiant Spur. Bantam Flyn, hot-headed squire and wielder of the renowned sword Coalspur, yearns to be one of them. When Flyn returns to the ancestral stronghold of the chivalric order, he finds the castle under siege from within by malevolent skin-changers in search of a changeling Flyn would die to protect. Suddenly Flyn finds himself on a quest to keep dear Pocket's location secret. By his side, Deglan Loamtoes, a gnome herbalist with an acerbic wit, and the brilliant but excruciatingly awkward Ingelbert Crane. Venturing into the unforgiving cold of the island of Middangeard, the trio find themselves close to the historical forces that shaped the very world. Hindered by giants, trolls, bands of berserkers, throngs of restless dead, and haunted by the howling