Rock, an Akita puppy raised in a secluded forest cabin by his mother—a revered guardian of woodland creatures—witnesses her demise after she is lured into a deadly trap by the tiger Killer and the fox Akamimi. Swearing vengeance despite his youth, he journeys to a city, joining a pack of street dogs who initially scorn his quest but rally behind him upon learning his purpose.

Tricked by Akamimi into a barrel hurled into the sea, Rock survives when a girl rescues him. He matures under her care until learning Killer now terrorizes captive animals from a city zoo. Returning with hardened resolve, he mobilizes street dogs and forest allies for a coordinated strike.

As an adult, Rock exemplifies resilience and tactical prowess, uniting forest and urban allies to dismantle Killer’s reign. His leadership peaks in a duel atop a speeding rollercoaster, where he topples the tyrant. Transforming from a grief-stricken pup into a strategic leader driven by justice, he channels vengeance into unity, rallying allies through loyalty and shared purpose.

His journey highlights boldness against overwhelming foes, adaptability across hostile cities and wilds, and the forging of alliances among rivals. Through isolation, betrayal, and battles, he emerges victorious, dissolving divisions among animals and cementing collective strength over solitary strife.