Ash joggt zusammen mit Rocko und Misty eine Straße auf der Seeschauminsel entlang. Ash nimmt seinen Trainingslauf sehr ernst, denn er bereitet sich auf die Pokémon-Liga vor. Vor lauter Trainingseifer verursacht er ein Verkehrschaos, das die Polizistin Rocky aber schnell in den Griff bekommt. Von Rocky erfahren die drei, das eine Riesenwelle, die nur alle zwanzig Jahre die Insel erreicht, erwartet wird. Und sie hören die Geschichte von Jan, einer Surflegende. Natürlich muss Ash sofort ins Wasser, um zu surfen...
Ash is running down the road and is hit in the face with muck splashed up by a car. Ash gets caught in the traffic with cars scattered everywhere. Officer Jenny clears the disturbance, and tells Ash of a great big wave that comes every twenty years called Humunga Dunga. They decide to go surfing, although Misty warns Ash to continue on his training. She joins in on the fun. Ash gets on the wave, but falls. Pikachu notices another Pikachu on the cliff staring into the sea. It is looking for big waves for its owner to surf. Then a big wave comes, but Ash can't move his foot to get to safety. The Pikachu named Puka alerts its owner named Victor of Ash. Victor and Puka swoop in to save him. When Ash recovers, Victor tells of getting Puka from the sea, and how he wanted to be like Jan who was the only man to ever ride Humunga Dunga all the way to a tall peak where he planted his flag. Meanwhile, Team Rocket successfully capture the two Pikachu and brought them into their Mecha Gyarados. They did not get far, as they were stopped and blown away by some real Gyarados. Both Pikachu were flung into the air. Ash saves his with Bulbasaur. Puka falls in the water, so Victor throws it a surfboard, and dives. They both get to the surfboard and Puka feels the large wave, Humunga Dunga coming. Ash and the Group make it back to the shore to watch Victor and Puka ride the wave all the way to the top of the peak matching what Jan did so many years ago.
במהלך שהותם באי סי-פורם, אש והחבורה לומדים על תחרות נעיצת דגל בסלע במים, דבר שקורה פעם ב-20 שנה.
אש מחליט לקחת את שארית היום לחופש ובמהלך הגלישה הוא טובע, וניצל ע"י גולש בשם ויקטור וע"י הפיקאצ'ו שלו.
ויקטור מספר להם איך פגש את הפיקאצ'ו שלו, ואת הקשר שלו לג'ן, וגם את החלום שלו לההפך לגולש כמו ג'ן.
אחרי התערבות קצרה של צוות רוקט, ויקטור ופוקה כובשים את הגל הגדול - הומאנגה דאנקה.
Mientras entrenan para la Liga Pokémon, los chicos conocen la historia de Víctor, un surfista que sueña con poder dominar la ola gigante ''Umungadunga'' junto con su Pikachu llamado Puka.
Quando Ash cai ao tentar surfar, Victor salva-o e fala-lhe da Humungadunga, uma onda gigante que passa a cada 20 anos. Conseguirão Ash e Pikachu dar a Victor a confiança de que ele precisa para apanhar a onda gigante?
Allenandosi per la Lega Pokémon, Ash prova il surf. Quando si sloga una caviglia in mare, viene portato in salvo da Victor. Riusciranno Ash e Pikachu a far ritrovare la fiducia in sé al surfista per affrontare la grande onda?
Da Ash bliver slået ud under surfing, redder Victor ham og fortæller ham om Humungadunga, en gigantisk bølge, som kommer hvert 20 år. Kan Ash og Pikachu give Victor den fornødne selvtillid til at fange den enorme bølge?