Before the events of the third film, Po [Jack Black] realizes that his father, Mr. Ping, [James Hong] is giving away his belongings as bonus gifts to customers, and has accidentally handed away his action figures of the Furious Five. As he searches for them, Master Oogway [Randall Duk Kim] asks whether there is any real difference between an accident and destiny, thus setting the scene for the story.
Ten years before the events of the first film, Tigress [Kari Wahlgren] is training under Master Shifu [Dustin Hoffman], but always seems to disappoint him by not conforming to his strict style. When Oogway and Shifu order noodles from Mr. Ping's restaurant, a young Po, who was left in charge of the restaurant while his father was absent, accidentally sneezes into Shifu's, making him sick. To make matters worse, a seemingly-unstoppable warrior named Boar [Jayden Lund] is en route to the Valley of Peace, defeating every kung fu master who opposes him. An incapacitated Shifu has no choice but to delegate responsibility to Tigress, giving her a scroll with the names of four warriors who can defeat Boar. At the same time, Po writes his own scroll with possible ideas for his future career, but he throws it out at his father's insistence. Tigress accidentally loses her scroll and mistakes Po's for hers.
Po's scroll contains the names of “Cleaner,” “Comedian,” “Dancer,” and “Doctor.” Tigress gathers Crane the Cleaner, Monkey the Comedian, Viper the Dancer, and Mantis the Doctor, David Cross , James Sie , Lucy Liu , and Seth Rogen respectively, to form a makeshift team for the trial. Tigress is impressed by the skills that they demonstrate, and assumes that Shifu will be proud of her. However, once she returns and the mistake is discovered, Shifu becomes angry, disappointing Tigress. As she sulks, Oogway encourages her to be herself rather than Shifu, so she decides to confront Boar. At first, she sticks to Shifu's style and is defeated, but she gets help from the others, who manage to stall Boar with their unique styles. In an epiphany moment, she finally embraces her own style and easily overpowers Boar with the help of her new teammates to defeat him. By chance, Po witnesses the entire fight, thus gaining his passion for kung fu. Tigress returns to the Jade Palace, where Shifu finally admits that he is proud of her, and gives her access to the training room to perfect her "Tigress" style. He also invites Crane, Monkey, Viper and Mantis to stay, deciding that their own styles can also be refined.
Back in the present, Po finds his toys with a bunny boy. While watching the boy play with the same passion that he had all those years ago, Po decides to let the bunny keep them. Po then admits to the Five that his toys are "where they're meant to be", and that, in fact, he already has the "real thing right here".
