Returning to the 1980s, waking up to surprisingly become a red carp! Relying on wisdom and evolutionary ability, he resolved crises in unfamiliar waters and finally regained human form. To repay the rescue of the aquarium father and daughter, he is determined to protect this home that had given him warmth. Facing consecutively appearing superpower animals, he bravely meets the challenge. How does an inconspicuous small fish ultimately become a protector everyone relies on?