On Whopper's way to the museum with his niece Alwyn Kushner and nephew Jasper Kushner, he shares the origin of Puppy Power, the remarkable ability for humans to communicate with the Pound Puppies and the Purries, setting the stage for a legend that stretches across centuries.
In the Dark Ages, around the year 950, a boy named Arthur and his dog Digalot stumble upon a single stone that houses two ancient relics: the mythical sword Excalibur and the Bone of Scone. When Arthur pulls Excalibur from the stone and Digalot pulls the Bone of Scone free, they discover a strange new bond between humans and dogs, enabling them to understand one another like never before. This moment sparks a chain of events that will echo through time, catching the attention of Sir McNasty, the Black Knight, who witnesses Arthur's rise to kingship and hatches a plan to conquer the world by seizing the bone. The bone, however, remains hidden, guarded by a colossal protector known as Big Paw, a figure of legend who looms large over the tale’s fate.
Fast-forward to the 1950s, the Bone of Scone sits in a museum in an unnamed American city. Tammy [Janice Kawaye] and Jeff [Joey Dedio], Pound owners, host a public adoption bazaar to celebrate the bone’s thousand-year anniversary, hoping to bring hope to neglected puppies. Enter Marvin McNasty, the direct descendant of Sir McNasty, determined to capitalize on the moment and claim a canine army for his own purposes. Marvin's arrival sets in motion a dangerous scheme: he intends to use a device called the Mean Machine to twist the puppies into vicious guard dogs, steal the Bone of Scone, and wield its power to dominate the world.
Whopper, ever the realist, tries to warn his friends, but Cooler [Ashley Hall], the leader of the Pound Puppies and a relative of Digalot’s line, refuses to believe him because Whopper has a habit of spinning tall tales. Undeterred, Whopper tails the henchmen as they move to steal the Bone, only to see the bone shattered in two, robbing Puppy Power of its full glory and setting off a race to recover both halves.
Whopper takes one half of the bone back to the pound, but the henchmen kidnap him and Collette [Cathy Cavadini], taking the half with them. Cooler and the rest of the Pound Puppies rally to mount a rescue and retrieve the stolen fragment. Collette and Whopper manage a narrow escape from McNasty’s lab, briefly reuniting with the Puppies, only to be recaptured again. The chase leads them into a rat-infested cave where most of the Puppies are suspended by a rope, saved at the last moment by the brave Purries, who pull them to safety. Undeterred, the Puppies and Purries press on, hoping to find their friends and restore Puppy Power.
Their journey brings them to a mire-filled stretch where salvation comes from an unexpected source: Big Paw, the legendary guardian, who agrees to help. As the plan unfolds, the group attempts to enter McNasty’s house, only to be captured and transformed into guard dogs—except for Cooler, who escapes by posing as a Purry, since McNasty is allergic to cats. Big Paw returns to town with Cooler and the Purries, rallying the town to reclaim the Pound and push back the intruders who have dug their way into the museum and glued the Bone of Scone back together.
With Puppy Power restored, Big Paw and Nose Marie [Ruth Buzzi] retrieve the Bone of Scone, and Whopper, along with his niece and nephew, finds themselves transported to the museum once more, drawn into a reunion that reaffirms the bond between humans and dogs. The Bone’s presence returns for a final visit as Whopper introduces Big Paw as a wondrous surprise for the children who doubted his reality, ending the adventure on a hopeful note and leaving a lasting message about faith, friendship, and the power of connection between species.
