The Celestian Alliance and their schools are at Windsor Castle for a field trip. As they were looking around The Crimson Drawing Room when they run into Ash, May, Brock, and May's kid brother, "Max". They were in the U. K to look for some Pokemon. After they greeted Sam to them, they greeted their Pokemon to them. Ash got out his Treecko, Taillow, and Corphish, May got out her Torchic, Beautifly, and Skitty, and Brock got out his Marshtomp, Geodude, and Vulpix. Sam adored Skitty's style, Betty Ann loved Beautifly's wings and was doing an assignment on butterflies, Kiki dug the Torchic and decided to lay off the chicken, Tucker loved the Tailow, Frank liked the geodude and Gary loved the treecko.
Suddenly their teacher, "Arthur Dent" came up and told them to catch up with the class. Gary whispered to them they the Pokemon need to find a place to play. So the Pokemon decided to play around Round Tower where they come across Team Aqua a wolf, a chameleon, and a panther. They were Wolf O'Donnell, Leon Powalski, and Panther Caroso. They were planning to steal the treasures from the castle. Suddenly a Lucario came in and fought them off. The ponies were looking around when they saw the action.
"Awesome a Team Rocket Brawl!" Rainbow Dash shouted as she started to attack.
"Oh my," Fluttershy said, "Rainbow you can't scare away the Pokemon."
"What have we here?" Wolf said,
"Your space aliens," Twilight said.
"Have you thought about joining a zoo party?" Pinkie asked, "Because you guys should go to The London Zoo."
"Oh please," Panther groaned, "The humans will think we're mascots."
"Plus animals would go great on bacon grease, except Pigma Dangar. You can't eat your own kind." Leon explained.
Panther started to develop a crush on Rarity, but Rarity refused to date him and placed lipstick on him, making everyone laugh.
"This is not funny guys!" Panther groaned.
Back in the castle, the students were finishing their tour when the Pokemon came along. Nigel was shocked and said, "So losers, who are these pets?"
"They're ours," Ash shouted as he ran to Pikachu.
"What's wrong?" Brock asked.
Everyone got confused and they decided to wait til they get back to their home.
When they got back they needed to know why were the Pokemon acting up since they told them to play outside. Cresselia came in and told them they saw Lucario. She explained that is was a servant to Sir Aaron in England. One day Queen Rin of Cameron was dying and gave her powers to him. While they were on the run, they were attacked by Skarmories. Lucario sensed his master's aura and wanted to go. Unfortunately, it was unsafe and Aaron imprisoned him in a staff hoping one day he'll come out in a worthy fighter.
They didn't know who freed Lucario from his staff. Cresselia showed them a vision of a girl with long red hair named, "Ginny Weasley". They needed to locate her fast.