While eating lunch in a grassy meadow, Ash and friends encounter a Mareep, which Brock describes as having a mild disposition, and the ability to store electricity in their fleece. The Mareep attacks Pikachu, who retaliates with a ThunderShock. More Mareep appear, and gather around Pikachu. It zaps them all, causing their wool to get very fluffy.
A young girl runs up, and attempts to get the Mareep to back off, but only one listens. Her mother and a Raichu arrive, and they succeed in freeing Pikachu. It turns out that Mary was supposed to be watching the Mareep, but as she daydreamed about an upcoming festival for Mareep, they escaped. She wishes to enter, but her mother says she is too young.
Later, Raichu and Pikachu are rounding up the Mareep, so they can be groomed in preparation for the festival. Team Rocket watches, with plans to sell the Mareep's wool to get rich. That night, Mary and her Mareep, "Fluffy", are practicing ThunderShock outside. They battle Ash and Pikachu, and Fluffy soon becomes worn out from using too many electric attacks. Mary was distraught: while focusing on winning her first battle ever, she forgot to take care of her Pokémon, a fact Ash reminds her of. Before dinner, Mary apologizes to Fluffy, and tells it she has realized she is not ready to compete in the festival yet.
In the middle of the night, a storm approaches. Ellen takes the group and the Mareep out to a cliff, to collect electricity and make their fleece look good for the festival. As their wool is fluffed up, Team Rocket attack, and capture all of the Mareep. Ash tells Pikachu to attack, but Team Rocket captures it, too. Mary's mother's Raichu uses Thunderbolt, but the electricity is merely absorbed by a special panel. Upon trying again, the panel short-circuits, and the balloon crashes. Pikachu and the Mareep are freed, but Raichu is exhausted. When Team Rocket send out Weezing and Arbok, Ellen uses the Mareep to battle. However, they are not strong enough, and Pikachu is still stuck in the cage. Mary tells her mother to concentrate the herd's energy onto Fluffy: her Mareep becomes supercharged, and, with the help of Pikachu, sends Team Rocket blasting off again.
The next morning, Mary's mom gives her an old Poké Ball and says she's ready to use Fluffy in the festival. Ash, Misty, Brock and Ellen cheer her on from the stands, as Mary's first battle commences.
