Sewaddle and Burgh in Pinwheel Forest (Japanese: タマゴからかえったあばれん！！ Pinwheel Forest! Sewaddle and Burgh!!) is the 18th episode of Pokémon: Black & White.
Ash and friends are travelling to Castelia City so Ash can battle the Castelia Gym Leader. While in Pinwheel Forest, they encounter a Sewaddle who swung right in and attack Pikachu with Bug Bite. As Ash followed Sewaddle through the forest in order to catch it (since he experience it's moves), they meet Burgh, the Castelia Gym Leader.
The heroes are near Pinwheel Forest. Cilan remembers it is stated that if they walk straight, they will be out in no time, but they might wander off and be lost, as in a maze. Iris thinks they won't get lost, as she is a forest expert. They see the forest is lush, the air is clean and the sunlight is strong. Suddenly, a bug hits Pikachu, knocking him out. Pikachu uses Thunderbolt, but the bug dodges, casuing Pikachu to hit Ash. The bug uses Razor Leaf, which Pikachu dodges. The bug uses String Shot to push itself to Pikachu, then uses Bug Bite on him. Cilan tells this bug, a Sewaddle, is known to be popular among fashion designers.
Ash goes to catch Sewaddle, who knocks him out using String Shot and covers him. However, Ash is more determined to catch it, so Pikachu uses Iron Tail to free Ash from the strings. Pikachu uses Thunderbolt on Sewaddle, who uses String Shot, levitating and fleeing away. Ash goes after it, while Iris and Cilan follow. Ash trips over, but still wants to catch Sewaddle. Iris and Cilan remind Ash they need to be back on the path. Later, the heroes cannot find the path, though Iris senses it is near. Suddenly, Iris hears the forest speak, though Ash thinks it is just his stomach being hungry. Ash and Cilan follow Iris, whose sense led them to a cliff. Iris sees they have to go to a high up to see where they should go next.
They come to a gigantic tree, so Iris and Ash climb it. They come out, but see something unusual. The object unseals itself, revealing to be a man, who shushes Ash and Iris, as they may scare the forest Pokémon. The heroes wonder what was the man doing there. The man replies he surrounded himself with nature, as he is an artist, who had a lack of inspiration. He wonders what are they doing here. The heroes admit they got lost, though the man tells he can show them the way out. Ash tells he wants to go to Castelia City to challenge the Gym Leader. The man replies that man is standing in front of them. The heroes are shocked, as this is Burgh, the famous Bug-type trainer. The heroes introduce themselves, so Burgh goes to make something, but is sad, as he thought he had an inspiration.
Iris wonders what was Burgh doing on the tree. Burgh replies he was making sketches, as the nature can be beautiful, for it shows old things can look new. The heroes see what he means. Suddenly, Ash gets attacked by Sewaddle, who comes on Burgh's shoulder. Burgh tells though Sewaddle is not his own, he befriended it during his search of inspiration. He tells one must know a Pokémon before trying to catch it. The heroes set up a camp, and as Cilan makes sandwiches, Burgh shows them introducing themselves to Sewaddle. The Sewaddle touches Burgh using the sensory knobs. Sewaddle greets Iris and Pikachu the same way, but bashes Ash. Burgh considers tackling to be some sort of greeting, though Sewaddle ignores Ash. Suddenly, Sewaddle leaves, displeasing Ash.
They see Sewaddle gazing at some leaves. Iris thinks it is listening to the forest, but a moment later, Sewaddle eats the leaves. They follow Sewaddle to a field, where it goes for a nap. Burgh, Iris and Ash lay on the ground and see the sky. Burgh tells seeing the sky makes one wonder how much the space is big. Sewaddle wakes up and eats the fruit. Iris thinks it is going to sleep again, though Burgh reminds it is a part of the natural cycle. However, a Woobat appears, who was also eating food. It uses Double Team, though Sewaddle's String Shot banishes the illusions. Another Woobat appears and both use Air Slash, though Ash takes the hit, protecting Sewaddle. Sewaddle and Pikachu use Razor Leaf and Thunderbolt, chasing Woobat away. Ash tells he did not feel a thing, while Sewaddle brings a fruit to Ash. At the camp, Iris serves everyone. Burgh wonders how did he know the fruit salad is his favorite food. Cilan tells he knows, being a Connoissuer.
At the giant tree, the heroes gaze at the shooting stars. Burgh asks Ash how much he learned at the journey, as Burgh saw the beauty of Bug-type Pokémon. They go to sleep, though Sewaddle goes into Ash's sleeping bag to sleep, though Burgh admits it is unusual for it to do that. Next morning, Ash sees that Sewaddle is on a Patrat. Sewaddle uses String Shot, levitating, but bounces onto a Deerling, while the heroes follow Patrat, thinking Sewaddle came in there. They see Patrat defending another Patrat, who is ill. The heroes think Patrat wanted to bring Sewaddle to cure Patrat, so Burgh gives it some bitter medicine, curing it. The heroes go out and see Sewaddle being attached to Deerling. Deerling comes to the cliff and jumps, though Sewaddle uses String Shot on Ash's arm, who tries to pull it. However, a wind blows, casuing Sewaddle to fall down to a river, so Ash jumps to save it.
Ash swims and holds Sewaddle. They both fall down the waterfall, but Burgh sends Leavanny, who pulls them up using String Shot. Ash thanks Burgh, though sees Sewaddle's cape is ruined. Later, Burgh pulls a leaf, which Leavanny modifies it and puts on Sewaddle. Burgh is impressed by Ash's heroism, while Sewaddle likes Ash for that fact. Sewaddle wants to go with Ash, so Ash throws the Poké Ball, catching it. However, the Ball is sealed, as Ash has seven Pokémon. Burgh takes the heroes to the Pokémon Center, where Ash leaves a Pokémon at Juniper's lab. He sends Sewaddle, who bonds with him. Burgh is inspired by this image. Burgh runs off to make a new project, promising Ash he will face him at the gym. The heroes bid farewell to him.
- This is the first time Ash catches a Pokémon with a team of six since catching Krabby early in Kanto.
- Professor Oak's Live Caster: Servine
- The "Who's That Pokémon?" is Sewaddle.