Ash, Misty, and Brock arrive at Goldenrod City and head to the Gym. There, Ash is dismayed to see a sign on the front declaring the Gym is closed today, but will reopen tomorrow. With nothing else to do, the three decide to explore the city. Brock suggests visiting the Goldenrod Galleria, but gets the group lost. Pikachu then gets an idea about where to go and heads towards a main street. However, he runs straight into a Clefairy. As Ash apologizes to the Clefairy, a girl runs down the street, asking if Pikachu is okay and picking him up to kiss him on the head.
The girl introduces herself as Whitney and offers to take the gang to the Galleria. She tells the group that the Galleria is far easier to get to if they take an Underground Path which doubles as a shopping arcade. Walking through the path, Whitney tells them that she discovered the route herself and Misty comments on how lucky they were to find her as a guide. However, Whitney winds up leading them further away from the Galleria. Eventually, the gang gives up on the Galleria and decides to head back to a hamburger stand they found earlier. Instead, Whitney inadvertently leads them to the Galleria.
Meanwhile, Team Rocket is inside the Galleria enjoying the snacks, believing them to be samples. They are soon approached by the store owner, who points out that only a small tray is free, and the trio needs to pay for the rest of the food. With no money to offer, the three are immediately put to work by the owner. Just then, they spot Whitney's Clefairy, who is separated from the others and walking around the store, and decide to grab it and send it to the Boss. Elsewhere, Whitney prepares to depart from the gang when she notices that her Clefairy is missing, and they begin looking for Clefairy. Team Rocket, however, is able to grab it first, but they encounter Ash and his friends and flee.
Team Rocket spots the station for the Magnet Train, a brand-new, super-fast monorail, and try to leave on it, only to learn it will be open for service in another year. This allows Ash and the others to catch up, forcing Jessie and James to steal a handcar and pedal away. However, their getaway is too slow, allowing Pikachu to simply walk next to them. When Ash orders a Thunderbolt, Jessie asks him not to and gives Clefairy back. Whitney thanks Ash, but then, Meowth takes the opportunity to grab Pikachu. Whitney orders Clefairy to use Metronome, which produces a Gust that grabs Pikachu right out of Meowth's paws and returns him to Ash. Ash tells Pikachu to use Thunder on Team Rocket, which Pikachu does. This activates the Magnet Train's magnetic propulsion systems, which sends Team Rocket shooting down the line.
Ash thanks Whitney for her help, and Whitney tells him that she would love to have a battle against him. Ash thanks her, but tells her that he is busy getting ready for a battle at the Gym the next day. At that moment, Whitney reveals herself as the Goldenrod Gym Leader, guides them back to the Gym, and reopens it. There, the referee announces that it will be a three-on-three battle, with a Plain Badge at stake.
Whitney starts off with Nidorina, and Ash responds by sending out Cyndaquil. Whitney orders a Poison Sting and a Tackle, but Cyndaquil counters with Flamethrower, eventually knocking Nidorina out. Whitney is shocked by the quick defeat and sends in Clefairy, who uses Metronome, but it winds up pulling out Splash. Cyndaquil uses Flamethrower again, but Whitney cannot bear to see Clefairy get hurt and withdraws it from the match.
Whitney then sends out a Miltank. Ash looks Miltank up on his Pokédex, which paints Miltank as a Pokémon who prefers not to battle. Whitney orders Miltank to use Rollout, and Miltank slams straight into Cyndaquil, sending it flying. Ash orders a Tackle and Cyndaquil attempts to hit Miltank, but is unsuccessful. Miltank turns around and repeatedly strikes Cyndaquil until it is knocked out.
Ash then sends out Totodile. Whitney orders another Rollout, which heads straight for Totodile. Ash orders a Water Gun, but it doesn't slow Miltank down and the Milk Cow Pokémon is rapidly approaching. Ash tells Totodile to get out of the way, but it is too late and Miltank hits Totodile with Rollout, knocking Totodile out. As Ash recalls Totodile, Miltank is still spinning around the battlefield, constantly gaining more and more power. Ash tries to think of a way to defeat Miltank, and Brock tells Ash that Totodile got Miltank wet, so an Electric-type attack should work. Ash sends in Pikachu and commands him to use Thunderbolt. Pikachu hits it, but it has no effect on the still-spinning Miltank. Whitney tells Ash that Miltank is spinning so fast, she is already dry. Ash decides to switch strategies and has Pikachu use Agility to try and outrun Miltank, but Miltank is still too fast and gets a direct hit. Pikachu tries to get up, but is hit again and defeated, giving Whitney the victory.