Ash and friends have arrived at Lily of the Valley Island. Ash wastes no time in registering for the competition. After registering for the tournament and checking in at the trainer's hotel, Ash goes to call Professor Oak. Knowing that the Sinnoh League is going to be tough with rivals like Barry and Paul competing, Ash decides it is best if he uses pokémon not only from his Sinnoh journey, but all his other past journeys as well. He sends his Sinnoh Pokémon to Oak's Lab and brings over five others from the lab in order to do some training. However, Team Rocket, pretending to be the transfer station aides, take off with Ash's Pokémon. They manage to stop Team Rocket, but now all his Pokéballs are scattered throughout the island! Now Ash, Dawn, and Brock must get them back before Team Rocket finds them!