Pokémon Ranger: Guardian Signs is the third in the Pokémon Ranger series. In the region of Oblivia, a gang of thieves known as the "Pokémon Pinchers" are stealing wild Pokémon and planning to use them for their own nefarious purposes. Two Pokémon Rangers, Summer and Ben, are sent to investigate. However, after an encounter with the Pinchers, one of them is kidnapped while the other is left stranded on an island. There they meet a Pichu with a ukulele, who teams up with them to help rescue its Pichu friends who have also been captured by then Pinchers.