A Birthday Kristy Will Never Forget!

Synopsis
The episode begins with and  traveling through a tunnel and when they emerge they receive a very cold welcoming, as they have now entered the snowy northern part of Sinnoh. Just ahead is Shelter Town, the final stop before Snowpoint City, so the gang decides to take a pit stop before moving on. While in a Pokémon Center, Dawn asks after a package that is due to be delivered to her, however Nurse Joy informs her it hasn't arrived yet. To pass the time, Dawn lets out of her Poké Ball to let her have some fun with the other Pokémon. Then, a stranger comes racing for Buneary and starts to hug and play around with it chanting the phrase "so cute", the stranger is a girl called Marilyn, who believes cute Pokémon are the best. She explains that her criteria for cuteness is that the Pokémon must be under 2 feet tall and must not have evolved, therefore Dawn introduces to Marilyn to see if she think Piplup is cute or not. Despite the fact that he meets her requirements, Marilyn discourages the fact he's cute and starts to remark on the features that turns off Piplup's cuteness, thus enraging Dawn and causing Piplup to be paralyzed in shock. After calling Dawn "Dawny", claiming it was a cuter name than Dawn, Marilyn is challenged to a battle, which she accepts.

Once the battle begins, Dawn uses Buneary causing Marilyn to infatuate over Buneary's cuteness, almost forgetting about the battle, she then sends out. At the start of the battle, Marilyn orders Cherubi to use when Buneary attacks with ... however Cherubi still recoils in pain even though Protect was successful. Brock realizes that this is simply Marilyn's attempt to stall the battle, making him angry and he orders her to battle properly or be disqualified. Marilyn tells Brock what she thinks battling is, which is the valiant of a Pokémon and how it stands up after being hit, thus enraging Brock and yells at her some more, she finally obeys Brock and defeats Buneary with a single. Marilyn is very pleased with herself, while Brock refuses to believe that a Pokémon's cuteness is their only asset in battle.

Nearby Team Rocket plans on taking Marilyn's Cherubi by tricking her to battle them, seeing as they have no Pokémon below 2 ft or unevolved, Jessie tells them to use, James hastily disagrees but has no choice. Jessie confront Marilyn and tells her she wants to battle and shows Mime Jr. to her, Marilyn however disagrees that it's cute crushing Mime Jr. feelings. Soon, James is comforting his devastated Pokémon while Jessie and Meowth work on the plan some more.

Brock tells Marilyn that he wants to battle her and says that she can pick the Pokémon she battles, allowing her to choose from and. Marilyn doesn't want to battle either of them because they aren't cute and asks Brock if he has another Pokémon. Brock releases and Marilyn wants to battle her, Brock accepts but as long as Sudowoodo and Croagunk battle too. Marilyn agrees so a 3 on 3 battle it is. Then James enters disguised as a Pokémon Battle referee offering his services and Marilyn, not realizing this is a little too convenient, asks him to officiate the battle.

After James announce the rules, Marilyn and Brock sends out Cherubi and Sudowoodo, Sudowoodo starts with which scores a direct hit, making Cherubi fall down dramatically. Marilyn however ignores the fact it hit and remarks on how Cherubi took the hit, causing Brock to scold her some more. Brock orders Sudowoodo to use, causing it to fall down dramatically too. Brock then tells Sudowoodo to use and Sudowoodo is soon sobbing on the floor. This causes Marilyn to start realizing the true battle strength of Pokémon. Wanting to move things along so he can see what other Pokémon Marilyn has, James declares the round as a tie as the two trainers return their Pokémon to their Poké Balls.

Brock sends out Croagunk while Marilyn sends out, and the battle restarts. Croagunk gains the upper hand against Chingling, this is all however a act played out by Marilyn to see Chingling take the attacks, Dawn then talls her to get to the point with Marilyn hastily obeying. Marilyn orders Chingling to use along with  and Croagunk is almost knocked out. Brock isn't willing to give up and encourages Croagunk to get up, and not wanting to let Brock down it does and uses, defeating Chingling. Brock tells how any Pokémon can be valiant regardless of their looks, unless the trainer bonds with their Pokémon. The two then return their Pokémon, with Brock congratulating Croagunk on an excellent battle.

With the lesson taught by Brock, she switches a Poké Ball containing a cute Pokémon for another Pokémon, which her friends mocked her for thinking it was her cutest Pokémon and thus changed her team to fit their perception. She then sends it out revealing it to be a, shocking Meowth and Jessie who are peeking from outside. Brock sends out Happiny, however Jessie and Meowth interrupts and tells Marilyn how disappointed they are with Shellder, then James starts to go into Marilyn's bag and steal two Poké Balls contain Cherubi and Chingling, angering Marilyn who orders Shellder to use to catapult itself to Team Rocket. After being hit by Shellder and dropping the two balls, Marilyn orders Shellder to use causing Team Rocket to be frozen rock solid, Happiny uses  to send Team Rocket Blasting off.

At the end of the day, Dawn receives the package from her mother. Inside is some clothing and a letter from Johanna telling Dawn that as Snowpoint City is very cold she has sent some winter clothing for her, Ash and Brock. Ash and Brock receive very snazzy thick blue jackets while Dawn receives a gorgeous pink coat, new boots and a scarf. Marilyn remarks on how great they look, and now ready to brave the cold weather the gang prepare to head into Snowpoint City so Ash can battle for his seventh Sinnoh Gym Badge...