Natsuya is an experienced Pokémon Ranger who is sent out on important missions. During a mission to saves Latios, Red Eye managed to stun Natsuya and the Mukuhawk he was riding on and he plummeted into the ocean.
Natsuya was tossed up on shore where he encountered Ukulele Pichu hiding behind a tree. The Pichu watched quietly until Natsuya approached it and tried to capture it.
During a mission to investigate the mysterious eruption in a volcano, Natsuya encounters a wild Heatran. He attempts to capture it but he looses his Capture Styler which James eventually finds. Natsuya managed to use the Ranger Sign for Feraligatr and the Feraligatr takes him to shore where Ash and his friends are camped out.
Natsuya introduces himself and that he is a Pokémon Ranger on a mission. Ash and his friend decide to help him out but as usual Team Rocket interferes. By working together, Natsuya is able to recover his Capture Styler and capture the wild Heatran.