"Digimon Adventure 3D: Digimon Grand Prix" is a short anime film that centers around a competitive racing event involving Digimon and their human partners. The story unfolds as Taichi "Tai" Kamiya, Yamato "Matt" Ishida, and their Digimon partners, Agumon and Gabumon, are invited to participate in the Digimon Grand Prix, a high-stakes race held in the Digital World. The event is organized by a mysterious figure named Piximon, who promises the winners a grand prize. The race takes place across a variety of challenging terrains, including deserts, forests, and icy landscapes, testing the skills and teamwork of the participants.

The main characters, Tai and Matt, are joined by other familiar faces from the Digimon Adventure series, including Sora Takenouchi, Koushiro "Izzy" Izumi, Mimi Tachikawa, Joe Kido, and Takeru "T.K." Takaishi, along with their respective Digimon partners. Each team must navigate the racecourse while overcoming obstacles and rivalries. The competition intensifies as the racers face off against each other, with some resorting to underhanded tactics to gain an advantage. The dynamic between Tai and Matt, often characterized by their friendly rivalry, is a recurring theme as they push each other to perform better.

The race is not without its dangers, as the participants encounter wild Digimon and environmental hazards that add to the challenge. The film emphasizes themes of teamwork, perseverance, and sportsmanship, as the characters learn to rely on each other and their Digimon partners to succeed. The climax of the story sees the racers nearing the finish line, with unexpected twists and turns that keep the outcome uncertain until the very end.

"Digimon Adventure 3D: Digimon Grand Prix" serves as a lighthearted, action-packed addition to the Digimon Adventure franchise, focusing on the camaraderie and competitive spirit of its characters. The film maintains a straightforward narrative, prioritizing the excitement of the race and the interactions between the human-Digimon teams. While it does not delve deeply into character development or complex plotlines, it offers an entertaining glimpse into the adventurous and competitive side of the Digital World.