When Joe Talbot's backpack is confiscated, Wishbone and Joe must confront a scary neighbor who owns a big, mean dog to get it back. This reminds Wishbone of the old English tale Beowulf. Imagining himself as the great hero Beowulf, Wishbone must defeat a series of monsters who are ravaging the kingdom. A lifetime of adventure takes him on a collision course with his greatest foe yet. And this time, more than courage will be needed to defeat such a monster - it will take a hero with four legs and the heart of a warrior!