Will and his brother Ned are on the long march from the Fens to North Wales, commandeered into the army of ditch-diggers heading west towards Flint, where they will be preparing the ground for the foundations of Edward I's new castle. They are nervous and rightly so—for not only is Ned a mute, whose abilities as a horse-whisperer and herbalist make him suspicious in the eyes of their English overseers, but they have been close to the enemy. Ned had been secretly taking lessons in music from Ieuan ap y Gof, an exiled bard, when the Welshman disappeared one night without warning not long before Edward's officers came recruiting. The boys find themselves a long way from home, virtually friendless and then captured by the enemy, suspected of treason and near killed before they are able to escape. When all appears lost, Will learns that love is sometimes harder to understand and to come to terms with than death itself.