Burning bridge. John Flanagan. 2020.

As the Kingdom of Araluen prepares for war against Morgarath, Will and Horace accompany the Ranger Gulan on a mission to Celtics. But Celtica’s villages are silent. Only an exhausted and starving girl called Evanlyn can tell them why: Morgarath has sent his foul creatures to enslaved the Celts. While Gillan rides swiftly back to Araluen to report this news to the King, Will, Horace and Evanlyn discover the true purpose behind Morgarath’s actions. The Kingdom is sure to be defeated in a surprise three-sided attack - unless they can find a way to prevent it.