At the end of spring, the folk of the western Wilderlands hold the traditional Moon Festival to celebrate the end of the harvest. This year, four years after the Battle of Five Armies, the Festival takes place near the village of Stonyford, and a fellowship of adventurers attend to share in the merriment and take part in the competitions. The prize – the Sickle of the Moon, a great artefact belonging to Beorn himself.
But before Frida and the Bride can take their places as trial-winners and perhaps win the prize, a hue and cry erupts – goblins have stolen the Sickle! Or so it seems at first, but Beran, Beli and the other adventurers soon uncover the truth – the sickle has been stolen by outlaws who are taking it north to give it to their master.
The adventurers give chase, pursuing the thieves for many days and more than a hundred miles up the banks of the Great River. Eventually they run the outlaws to ground on the Falrock, an island on the river, and do battle atop a great fallen log that bridges the isle and the river-bank. They overcome the bandits (most of whom seem to be slaves and thralls, rather than truly evil men) and their cruel leaders to recover the Sickle; they return it to Beorn and are celebrated by the villages that he protects.