Appearing before Pikachu and friends is the keyring Pokemon, Klefki. Inserting a mysteriously shaped key into the keyhole floating in the air, a very mysterious portal appears! Klefki has the key to go to various worlds. What kind of world will the key that Pikachu holds lead to?
| Actor | Role |
|---|---|
 Ikue OtaniPikachu (voice) | Pikachu (voice) |
 Megumi SatouDedenne (voice) | Dedenne (voice) |
 Yuji UedaKeromatsu / Sonans (voice) | Keromatsu / Sonans (voice) |
 Megumi HayashibaraFokko (voice) | Fokko (voice) |
 Hitomi NabatameHarimaron (voice) | Harimaron (voice) |
 Shin-ichiro MikiLuchabull (voice) | Luchabull (voice) |
 Inuko InuyamaNyarth (voice) | Nyarth (voice) |
 Kenta MiyakeMaaiika (voice) | Maaiika (voice) |
 Rikako AikawaCleffy (voice) | Cleffy (voice) |
 Chika AnzaiVictini / Amarus (voice) | Victini / Amarus (voice) |
 Kiyotaka FurushimaChigoras (voice) | Chigoras (voice) |
 Yuka TerasakiOnbat (voice) | Onbat (voice) |
 Tomoko KanedaJirachi (voice) | Jirachi (voice) |
 Chinatsu AkasakiShishiko (voice) | Shishiko (voice) |
 Rica MatsumotoSatoshi (voice) | Satoshi (voice) |
 Mayuki MakiguchiSerena (voice) | Serena (voice) |
 Yuki KajiCitron (voice) | Citron (voice) |
 Mariya IseEureka / Manaphy (voice) | Eureka / Manaphy (voice) |
 Mayu WatanabeNarrator (voice) | Narrator (voice) |