Twelve-year-old William is beginning to wonder if Jason is still his best friend. When Jason challenges William to “jump the trains,” William is terrified but feels he must prove himself. The opportunity arises when his former housekeeper sends him a magic token that once again takes him back to the mystical world of Sir Simon’s castle, this time with Jason. There they face a dangerous army of rats and their gigantic leader. Once, William was a hero in the castle. Now it’s up to him to destroy the rats and save the kingdom in the final battle for the castle.