Ash, eager to extend his World Coronation Series winning streak, has traveled to the Fighting Dojo in Saffron City to challenge the Karate Master. However, while his Riolu is sparring with the dojo's other Pokémon, Ash is informed that the Karate Master is currently in the middle of another battle. Meanwhile, Goh has trouble choosing whether he'd want a Hitmonchan or a Hitmonlee from the dojo, as he's only allowed to choose one. Suddenly, Ash's Rotom Phone alerts him of the presence of another World Coronation Series participant, and he realizes that the person must be inside the dojo. However, just as Ash is about to enter, a fainted Hitmonchan flies through the doorway and lands on top of Ash. The Hitmonchan turns out to belong to the Karate Master, who's just been defeated by his challenger. The other Black Belts present express their amazement towards the strength of the challenger's Grapploct, a Pokémon that Ash hasn't heard of before.
Just then, the challenger's Rotom Phone informs her of Ash's presence, and Ash eagerly issues a challenge for an official World Coronation Series battle, which is accepted. Ash's opponent introduces herself as Bea from Galar and requests to use the dojo as a battlefield, which the Karate Master agrees to. Goh asks if he can receive a Hitmonchan or Hitmonlee from here, which the Karate Master confirms, but Goh is surprised to learn that he must defeat the Karate Master to do so. However, Ash and Bea's battle comes first. Karate Master tells Ash and Goh that Bea is a Fighting-type Gym Leader from Galar and a master of Galar Karate, who travels the world to challenge dojos in her pursuit of greater strength.
Goh takes note of the fact that Bea's ranking of 751 is notably higher than Ash's 890. Ash, however, is not worried, as he's won his every World Coronation Series match so far. Facing a Fighting-type Gym Leader reminds Ash of how he beat Korrina the other day. To Ash's surprise, Bea recognizes the name and mentions she has both battled and beat Korrina as well. She calls her entirely too overconfident, and refuses to elaborate on what she means, irritating Ash. She asks why Ash signed up for the competition, and Ash says that he's aiming to battle Leon, which Bea is also aiming for.
A Drone Rotom appears to referee the battle, which will be two-on-two. On Rotom's signal, the Pokémon are sent out. Ash chooses Farfetch'd, while Bea chooses Hawlucha. Hawlucha begins the battle by using Hone Claws to power itself up. Farfetch'd uses Night Slash, which Hawlucha avoids before hitting Farfetch'd with a Karate Chop, causing it to accidentally drop its leek. Hawlucha then follows up with Flying Press, which Farfetch'd avoids while retrieving its leek. As Hawlucha charges towards it, Ash has Farfetch'd use Brutal Swing. The move connects, but while Farfetch'd is still spinning, Bea tells Hawlucha to finish it with Flying Press. Using Farfetch'd's leek as a springboard, Hawlucha jumps into the air, and while Farfetch'd is still recovering from the spinning, the Flying Press connects and knocks the Wild Duck Pokémon out.
As Ash recalls Farfetch'd, Bea surprises everyone by also making a switch, recalling Hawlucha in favor of Grapploct. Goh remarks that this is the Pokémon the Karate Master was battling when they arrived, and the Karate Master remarks that his Hitmonlee and Hitmonchan didn't stand a chance against it. Before Pikachu can step onto the battlefield, Riolu steps forward, wanting to battle instead. Ash accepts Riolu's request and declares that Riolu is his second Pokémon. Riolu begins with a flurry of Vacuum Waves, but Grapploct uses Detect to dodge them all and charge forward, preparing to use Close Combat. Riolu uses Double Team, but Bea has Grapploct dispose of the illusory copies by using Liquidation. Riolu tries to block the move, but the flurry of blows is too much for it to block, and the Emanation Pokémon takes heavy damage. Ash tries to risk a close-range attack with Force Palm, only for Riolu to barely escape being ensnared by Grapploct's tentacles.
Ash gets an idea and tells Riolu to use Force Palm below of its feet, sending out a cluster of floor pieces to distract Grapploct. However, when Riolu tries to charge in with another Force Palm while Grapploct's back is turned, the tentacle around its waist snatches it from mid-air. Grapploct ensnares Riolu's body and arms in a tight Octolock, with Bea criticizing that Ash's strategy has too many wasted movements. Ash notices that Riolu's legs are still free, and has it use them to jump, genuinely surprising Bea for the first time. Riolu jumps upwards and turns around mid-air, causing Grapploct to hit the ground first and unintentionally release its grip from Riolu.
Grapploct next uses Liquidation, which Riolu counters with Reversal, a move that grows in power the more damage the user has taken. The two attacks clash and push both Pokémon back, but as Riolu falls on its knee from exhaustion, Grapploct charges in and ensnares Riolu in another Octolock, this time making sure to bind its legs as well. Bea tells Ash to surrender, but Ash refuses to give up. With no other choice, Bea has Grapploct use a close-range Liquidation, defeating Riolu and granting Bea a near-flawless victory. Ash is crushed by his clear loss, and as his ranking drops to 930, Bea leaves the dojo after thanking the Karate Master for letting them use it. Next up, Karate Master addresses Goh, reminding him that now it's his turn to battle him.
Later, Ash's Farfetch'd and Riolu are healed at the Pokémon Center, and Goh shows off the Hitmonchan he managed to win for himself. Ash apologizes to his Pokémon for letting them down, and swears that he will have his revenge match against Bea.