Pokémon - S01

On a new day in the Kanto region, Satoshi gets invited by Professor Yukinari Ookido to Professor Sakuragi's lab-opening ceremony in Vermillion City. During the ceremonial speech, Professor Sakuragi gets an alert about a possibly rare Pokémon appearing in Vermillion City's harbor, so Satoshi and the other trainers rush there hoping to find the mysterious Pokémon. At the harbor, they find Lugia, a Legendary Pokémon, fighting other trainers. Noticing the other trainers' tactics, Satoshi has his partner Pikachu hit Lugia with a Thunderbolt attack. Unfazed, Lugia flees, but not before Satoshi determinedly jumps onto its back. To Satoshi's surprise, he meets another boy, Gou, who jumped onto Lugia's back too. The two ride on Lugia's back as it takes them on a bizarre adventure across the seas. After it lets the two back on the ground, Satoshi and Gou say their farewells to Lugia and return to Sakuragi Institute. Impressed by Gou's findings and Satoshi's insight from their encounter, Sakuragi asks the duo to be his new research partners. And so the duo's journey begins, traveling across multiple regions to meet many new Pokémon, including ones that can Gigantamax!