While Ash, Misty, and Brock were busily walking along a wide road, they spotted a green Pokémon flying overhead. Ash searched it up on his Pokedex, which stated: "Yanma: the clear wing Pokemon. Through the use of its two large eyes, Yanma can see in all directions at once." The green Pokémon, whose name was Yanma flew towards Ash, and took off with his Pokemon League hat. The Yanma flew down to a boy, but getting scolded for flying off at it's own free will. It's trainer stated to Ash and his friends that he couldn't keep his Yanma from flying off. Just as he was saying this, Yanma took off once again, flying to a nearby town. Everyone in the town started closing their windows and shops, afraid of the Yanma.
Ash, Misty, Brock, and the Boy come to the town, and Yanma flaps its wings with great force that a nearby window started breaking. Yanma held still long enough for the boy to get it back into its Pokeball. The owner of the store walked over to the boy, saying very sternly that his Yanma broke his windows once again. Zachary explained time to time again that he kept telling Yanma to not beat its wings so fast, particularly in a town, but the man would not listen to his reasons, tired of his excuses. The owner settled the matter once and for all by talking to the boy’s father, being closely followed by Ash, Misty, and Brock. At the greenhouse, the boy’s father was found apologizing to the stricken owner.
The storekeeper was complaining that the Yanma kept breaking the windows continuously, finally getting to the point where Yanma should be got rid of immediately. Zachary’s dad explained to his son to get rid of Yanma at sunset. Misty asked why Zachary chose a Yanma of all Pokemon, but only to be touched by the story which was about to unfold. Zachary said tearfully that on one fateful day, he and his father were bringing stacks of glass to a town. On the way home, Zachary spotted a hurt Yanma, lying unconscious in the rain. He took it home, fed it, and made it stronger. After that, Yanma started breaking the glass in his dad’s Glass factory. After telling the story, Zachary brought Yanma out into the forest, and decides to let it go after a small snack and a wave goodbye. Zachary runs off, and trips. Ash, Misty, and Brock caught up.
He said that he didn't want to let Yanma go, but he had to, or else it would have kept causing trouble. He ran back to the place where he let Yanma go, only to find it missing. Team Rocket spotted Zachary’s Yanma when they were looking for Pokemon. They snuck up behind it, and caught it vigorously. They tied a rope around it, just to find that Yanma was trying to fly away. It flapprd its wings with immense speed, breaking the windows in a nearby building. James looked up Yanma in his Pokemon guide, and read out that Yanma can break windows from loud shock-waves. Jessie stated that if they could make Yanma break some windows, they can make some cash. Through the quiet, but happy town, Team Rocket ran through the houses, with Yanma breaking all the windows. Everybody wanted new glass to replace the broken ones, having dreams coming true when Team Rocket came up, holding a sign that they were from the "Glazed-Over Glass Company".
James opened an ice cream cart, and pulled out a pane of glass which was really a strip of solid ice. After being questioned by the curious crowd of why they kept their glass inside an Ice Cream trolley, Team Rocket stated that using an ice cream cart was proof of how cool their glass was, and how they specialised in frosted windows. Everyone in the town hired panes of glass to replace the broken windows, only to give Team Rocket large amounts of money. Later, while having their lunch, Jessie stated gleefully that their rich plans were brilliant - Breaking all the windows, then coming along selling sheets of ice. Then, by the time the people realized that they have been tricked, Team Rocket would have left. Jessie viciously grabbed a donut away from Yanma. Yanma remembered Zachary - and how it could eat all it wanted.
Ash, Misty, and Brock were hiking through the forest, looking for Yanma. They spotted a Pokemon Center, and entered. They spotted Zachary’s dad, and they ask if he’s seen Yanma, but having no luck. Back at the town, Zachary ran up to a group of people, and asked them if they have seen Yanma. They grabbed him, and told him that after his Yanma broke their windows, a group of con artists came and sold them sheets of ice that resembled sheets of glass, thinking he, Zachary, was part of the skeem. They took Zachary by the scuff of the neck to see his dad. Back at the Pokemon center, they found out that Zachary’s dad was an expert at making stained glass windows. Then, the people from the town ran up, telling Zachary’s dad about the fake glass plan. Team Rocket tried doing the same thing at the Pokemon Center, but the People there explained what they were up to. Team Rocket threw off their disguises, stating their infamous motto
Ash angrily sent out Chikorita, closely joined by Misty's strong Poliwhirl. Jessie however, chose Yanma. Zachary’s dad said that if they battled near the Pokemon Center with Yanma as they're fighting Pokémon, the stained-glass window will be broken to pieces. Jessie was ruthless. She reasoned that if they didn't want the windows broken, they should not bother battling. While Ash was thinking, Arbok uses Wrap on Chikorita and Poliwhirl. Zachary called Yanma back into his Pokeball, and Victreebell ran towards it. Zachary grabbed it, only to be found on the ground when he was knocked backwards. Chikorita used Vine Whip, and Poliwhirl used Water Gun. Arbok was knocked out, but Victreebel’s Razor Leaf attack sent both opponents flying.
Zachary’s dad stated to him that Yanma has to proceed in battle, even though the stained glass will be destroyed. He says that it was important for Zachary to learn if he and Yanma can ever be a team, since it would be Yanma’s first battle. After thoughtful thinking, Zachary agrees. Zachary ordered Yanma to use Sonicboom on Arbok, sending it flying into the air. Yanma did it again, while Victreebel used it's Razor Leaf attack. Yanma tried a Double Team attack, and Chikorita, Poliwhirl, and Yanma tackled the confused Pokémon altogether. Team Rocket was sent flying into the air, twinkling in the deep blue sky. Miraculously, Yanma's participation in the battle did not break the Stained glass windows of the Pokémon Centre. Zachary’s dad finished fixing in the last pane of glass, and it looked more elegant than before.