Po is gearing up to become the spiritual leader of his Valley of Peace, but also needs someone to take his place as Dragon Warrior. As such, he will train a new kung fu practitioner for the spot and will encounter a villain called the Chameleon who conjures villains from the past.
Over the course of ten days and 435 miles, an unbreakable bond is forged between pro adventure racer Michael Light and a scrappy street dog companion dubbed Arthur. As the team is pushed to their outer limits of endurance in the race, Arthur redefines what victory, loyalty and friendship truly mean.