On the way to Pewter City and then the Battle Pyramid, Ash and May encounter a golden Sudowoodo. Ash tries to catch it, but fails. In town, Brock doesn't believe them, but a bunch of people do and want info. After the people mob them for information, they retreat with a boy named Keenan where they learn that Sudowoodo is his. Keenan tells them for some reason Sudowoodo will not come back to him. Meanwhile, Team Rocket hears this and decides to capture Sudowoodo, however the townspeople also have their eyes on Sudowoodo! It turns out that Sudowoodo is gold because of an experiment that Keenan performed on it which is why it will not go back to Keenan. Can Ash and friends stop Team Rocket and the townspeople from taking Sudowoodo? And can Keenan get the chance to reconcile with his Pokemon?
The heroes stop for a break. May and Ash go to get water. May sees the beautiful lake and wishes to rest. Suddenly, they spot a golden Sudowoodo. Ash decides to capture it. Pikachu uses Thunderbolt to knock it out and Ash throws his Poké Ball, but Sudowoodo pounds it back to Ash, knocking him out and runs away. Later, Ash and May try to convince Brock they saw the golden Sudowoodo, but he denies the fact. Max is starving - Ash and May did not get any water, though Brock replies to him they will eat in a restaurant. However, they spot it is a bar full of shifty characters.
May sees a poster of Lilian - there will be a Pokémon Contest in Mulberry City. Since it is on their way to Pewter City, Brock tells her it is fine to go there. May wishes only to get the golden Sudowoodo, to which the people got her attention. They heard about the golden Sudowoodo and tell there is a thing in the mountains that will turn any Pokémon gold if they eat it. The heroes are cornered, but they pass underneath them to follow a boy. Team Rocket heard the myth and want to get the golden Sudowoodo. The boy leades them inside his house and introduces himself as Keenan. The heroes introduce themselves as well, and Ash and May confirm they saw the golden Sudowoodo. Keenan believes them as that Sudowoodo is his.
He shows them a picture of himself and his (golden) Sudowoodo. Team Rocket hear them and Meowth thinks it would be good to capture the golden Sudowoodo for boss' golden collection. Keenan tells his Sudowoodo is strong against Water-type Pokémon. Max wants to know from where it came from, but Keenan does not know. Brock tells that Onix evolve to Steelix, so the Sudowoodo must have gotten the gold on itself from a nearby mine. Ash says they should help Keenan to find the golden Sudowoodo, as he helped them to get out of the bar, despite Keenan not wanting any help. Team Rocket arrived to the lake and Jessie thinks they need bait to get Sudowoodo. Throwing a normal Sudowoodo in the lake would make a goddess to appear and because of Jessie's beauty, she'd give her the golden Sudowoodo. Since they don't have any Sudowoodo, they dress Meowth as a one. Just when they throw Sudowoodo (aka Meowth), the golden Sudowoodo appears out of the lake.
Meowth hears Sudowoodo talking some nonsense, though Jessie reminds them they need to capture it. Meowth equipes Jessie with gear and she goes in the lake and captures the golden Sudowoodo. The heroes arrive and demand Sudowoodo back. Jessie tells them she got the Sudowoodo and it is her own. Keenan calls Sudowoodo back, but Sudowoodo goes behind Jessie's back and Jessie is affected by the laser. Ash tells Keenan that Sudowoodo does not want to go back, so Brock sends Bonsly to talk to it. Bonsly talks to it, resulting in the golden Sudowoodo being upset and running away. Keenan goes to get him. The heroes ask Keenan if he did something that made it upset. Keenan confesses that he did an experiment to make it stronger. He tried to make it stronger against Water-type attacks. He succeeded, though the side effect was Sudowoodo was all golden and upset.
Keenan tells them he found a way to get the gold off, but cannot do it when Sudowoodo is running away all the time. The heroes will still help him get Sudowoodo back, to which Keenan is grateful. Sudowoodo comes out of the bushes, but is ambushed by Team Rocket. Sudowoodo runs away to the town, dodging the nets Meowth fires away, into the bar. Sudowoodo greets the people, but runs away when they go to get it. Keenan spots Sudowoodo and tells it he found a way to change it back, but Sudowoodo turns to a different alley, not listening to him. Though the townsfolk pass, Sudowoodo is attacked by Team Rocket's robot. Sudowoodo evades and the heroes arrive. Pikachu uses Thunderbolt on the machine, but with no effect. The robot goes to grab Sudowoodo, but Keenan uses his shovel to block the robot. However, the robot attacks him and knocks him out. The robot goes to get Sudowoodo, but Keenan does not give up, as he holds the robot's leg. Suddenly, Sudowoodo tackles the robot and follows with Brick Break, destroying the machine. Pikachu uses Thunderbolt to blast Team Rocket off.
Keenan wants an apology for Sudowoodo, to which it gives him. The townsfolk go to get Sudowoodo, so the heroes, Keenan and his Sudowoodo run away back to his house. Inside, Keenan pulls a lever and Sudowoodo is changed back to its original state. The heroes, Keenan and Sudowoodo walk though the town, while the townsfolk still search for the golden Sudowoodo. In the end, Keenan promises not to let his Sudowoodo go and May is excited to have a chance to get her last ribbon in Mulberry City. The heroes leave Keenan and Sudowoodo, who wave goodbye to them.