Ash and his friends arrive at Mauville City and immediately proceed to the Mauville Gym so Ash can battle for his Dynamo Badge. Upon arriving they are whisked away at high speeds (Wattson the Gym Leader is controlling the speed) on a platform along a long corridor and over some water till they meet what appear to be a Raikou. Thinking it will attack the group, Ash immediately takes action and has Pikachu attack it with Iron Tail. The head of the Raikou falls off and it is shown that the Raikou was no more than a machine. Wattson, the Mauville City Gym Leader along with his assistant Watt promptly appear out of a door on the side. Wattson appears delighted with Ash for being able to defeat the mechanical Raikou. At the same time Team Rocket discovers what appears to be an abandoned power station. Thinking that they could use this as a base for their operations in the Hoenn region, they proceed to enter only to find out that it's filled with Voltorb and Magnemite. Dejected, Jessie and James leave only to be stopped by a scheming Meowth who informs them that the Voltorb and Magnemite would make a great present for the boss in one of his boss fantasies. The episode then cuts back to Ash and Wattson ready for their Gym Battle. Wattson announces that the match will be a three-on-three and he'll be using his Voltorb, Magnemite, and Magneton and as he's been training with them all for years Ash should expect a tough battle. The gang is shocked that Wattson disclosed which Pokémon he'll be using, but then starts to discuss Ash's choices of Pokémon to use when Pikachu, more eager than ever, leaps into the battlefield determined to go first and Ash agrees. Wattson laughs, happy that Ash is using an Electric-type against his and commands Magnemite to use Swift. Ash responds by having Pikachu then use Thunderbolt, which is so powerful it knocks out Magnemite with a single hit! Wattson is stunned, but still jovial and sends in Voltorb telling it to use Screech. Ash has Pikachu use another Thunderbolt and Voltorb is also taken out in a single hit. By now, everyone is surprised at Pikachu's amazing performance, while Wattson has lost most of his jolly nature and, now determined to defeat Ash, angrily sends in Magneton ordering a Zap Cannon. Ash now has Pikachu use Thunder, which easily plows through the Zap Cannon and knocks Magneton out instantly. Ash is the winner, and no-one can believe just how well he did. Wattson is completely shell-shocked at being defeated so easily, however he attempts to put a brave face on and awards Ash the Dynamo Badge before leaving, leaving Watt very concerned. However Ash doesn't get a chance to celebrate his win as he notices that Pikachu's not feeling well. The scene then cuts to the Pokémon Center where Wattson is sadly handing his Pokémon over to Nurse Joy so they can recover from the battle and informs her that Watt will be sent to pick them up. Nurse Joy appears confused at seeing the usual bubbly and warm Wattson seeming so somber and dejected, but Wattson just tells her he's having a bad day before leaving. Soon after he's gone Ash, Watt and the others rush into the Pokémon Center asking Nurse Joy to check out a now clearly sick Pikachu. We then see Wattson sitting by what appears to be a lake, thinking about the disastrous battle with Ash and concluding he is no longer worthy of the title of Gym Leader. An Electrike then comes towards him and starts playing with Wattson. Back at the Pokémon Center Nurse Joy tells the group that Pikachu's electric levels were higher than usual and asks Ash if he's been exposed to any high voltage recently which makes Ash disclose the incident with the mechanical Raikou. Nurse Joy informs the group that Pikachu is overcharged and this enables Pikachu to have a lot of power in his electric attacks for a short period of time. Brock then is able to figure out that this is reason for the shocking victory over Wattson. Pikachu recovers. Wattson's assistant then storms into the Pokémon Center asking if Nurse Joy has seen Wattson as he seems to have disappeared. She recalls the incident a few minutes ago where he dropped off his Pokémon somberly, then works out that Wattson is at his favorite location, a lake by the abandoned power plant, and coincidentally the same location as Team Rocket. Back at the lake Electrike shows Wattson his Thunder Wave. Wattson then sees Team Rocket stealing the Voltorb and Magnemite from the power plant in a new electric proof machine. The group arrives at the scene and confronts Team Rocket. Team Rocket steals Pikachu and Electrike and then attempt to escape. Ash is about to follow them to retrieve his Pikachu but Wattson stops him and tells him that he has a plan. Team Rocket is overjoyed with the apparent victory over the twerps. Suddenly out of nowhere the same mechanical Raikou appears right in front of Team Rocket. The group then shows up as well. Thinking it's a real Raikou, Team Rocket is petrified and becomes too scared to attack it. Torchic and Forretress then unsuccessfully attack the machine. Pikachu and Electrike then use Iron Tail and Bite respectively to try to break the cage they're in. Team Rocket eventually decides to try to attack the Raikou and have Seviper launch a Poison Tail attack on it which immediately destroys it. Right at that moment the Pokémon they just stole have just managed to break the cage and escape. Seviper and Cacnea attack Pikachu, however Pikachu easily beats them. Dustox is then sent out and beats Pikachu but Electrike then steps in and beats it. Pikachu then uses Thunderbolt to send Team Rocket flying. Ash then confesses to Wattson the reason why he was able to beat Wattson so easily and offers to hand the Badge back to Wattson. However Wattson refuses to accept the Badge back insisting that Pikachu deserved it for his efforts in helping save the Pokémon at the power plant. Wattson and his assistant then say their goodbyes to the group and Ash promises Wattson that he'll battle him again in the future.