As the first round of the Manalo Conference is about to begin, Ash and Faba are the first pair of Trainers to face each other. Caster mentions how Ash has cleared all four grand trials, while Faba is one of Aether Paradise's elite and a Psychic-type user. Hala, refereeing the match, asks both Trainers to send out their Pokémon, and Faba sends out his Hypno, while Ash chooses Pikachu. However, before Pikachu can leap down from Ash's shoulder, Faba secretly has Hypno use Psychic to pick one of the Poké Balls on Ash's belt and drop it on the field, causing Meltan to come out, much to Ash's surprise. However, upon seeing that Meltan likes the crowd's attention and wants to battle, he decides to use it instead of Pikachu.
As Caster informs the crowd that Meltan is a newly discovered species of Pokémon, Faba remembers the previous night, when he secretly spied upon Ash's team to determine which Pokémon was the weakest. Settling on Meltan, he resolved to bring it out, wanting to make sure he would get to battle the Masked Royal. Ash's classmates, thinking Ash chose Meltan on purpose, are wondering if he has a plan for it. Caster explains that the first round consists of one-on-one Single Battles before Hala officially starts the match. Meltan attacks with Flash Cannon, but Hypno avoids it. Meltan tries again with Headbutt, which is blocked by Hypno's Reflect. Unaware of Meltan noticing Hypno's pendulum, Faba has Hypno use Hypnosis. Ash tells Meltan not to look, but instead, it leaps forward and happily latches onto Hypno's pendulum. Hypno stops attacking and furiously tries to shake Meltan off, but by the time that happens, Meltan has already melted a part of the pendulum away, much to the shock of both Faba and Ash. Recovering from his own shock, Ash then has Meltan attack with Flash Cannon, which hits the dismayed Hypno head-on, defeating it and giving Ash the victory. Faba tries to protest, but Hala says Meltan simply made use of its natural abilities, making the move perfectly legal. Upon exiting the battlefield, Ash encounters Ilima, who congratulates him on his victory before heading out for his own battle.
The second pair of Trainers, Ilima and Guzma, enter the battlefield, with Ilima's fan-girls cheering for him. Caster points out that Ilima has competed in the Kalos League, making him a favorite to win the tournament. He also introduces Guzma, who, while unknown compared to Ilima, managed to clear the preliminary round without taking a single hit. In the crowd, Tupp is annoyed at Ilima and leads his fellow Team Skull Grunts into a cheer for Guzma.
Ilima sends out a Kangaskhan, while Guzma sends out his Scizor. Hala tells both Trainers to battle fairly before starting the match. Kangaskhan begins the face-off with a Power-Up Punch, avoiding Scizor's Bullet Punch to deal the first hit. An orange glow surrounds Kangaskhan to signify her Attack power rising, and Rotom points out that Power-Up Punch gets stronger with each hit. Kangaskhan uses Power-Up Punch again, but Guzma has Scizor avoid the attack with Agility. Ilima compliments Guzma's skills, but then reveals a Key Stone, Mega Evolving Kangaskhan into Mega Kangaskhan. With the child Kangaskhan now temporarily grown up thanks to Mega Evolution, the mother and child attack Scizor together with Power-Up Punch, before following up with Rock Slide. Although Scizor dodges the mother's rocks with Agility and smacks the child's rocks aside, it is then struck by a simultaneous Low Kick from both of them.
As Ilima seems to have Guzma backed into a corner, he orders another Power-Up Punch, but Guzma orders Scizor to dodge backwards, avoiding the child's punch. As the mother prepares to attack, she suddenly hesitates, and Guzma takes the opportunity to have Scizor use X-Scissor on her. As the Kangaskhan pair attacks again, Scizor once again dodges to a specific direction, avoiding the child's attack and causing the mother to hesitate, leaving her open for another X-Scissor. Sophocles wonders why Scizor's attacks suddenly started hitting, and Kiawe explains that Scizor is now constantly seeking a position where it has both of its opponents in a straight line. With the child in the way, the mother will hesitate to attack in fear of hurting her offspring, giving Scizor a chance to attack her. With the tide of the battle turned, Kangaskhan is starting to get worn out, and Guzma orders one more X-Scissor to finish the job. Ilima tells Kangaskhan to dodge, but she's unable to out of exhaustion, and is struck down. As the child Kangaskhan reverts to its regular form and climbs back into its pouch, Hala declares Guzma the winner. In the stands, the Team Skull Grunts celebrate and Ilima's fan girls cry in disappointment, while Caster exclaims his surprise at the front runner getting defeated on the first round.
The third battle is between Hau's Alolan Raichu and Samson Oak's Alolan Exeggutor. With its superior Speed, Raichu is easily able to keep ahead of its opponent. Hau orders a Thunderbolt, but Exeggutor easily endures the attack. Samson has Exeggutor counterattack with Dragon Hammer, but Raichu dodges it with Quick Attack, before using Focus Blast, causing the tall Pokémon to topple down in defeat. In the stands, Hala looks proudly at his grandson as Olivia declares Hau the winner.
As Lana and Mallow walk towards the battlefield, Mallow expresses her nervousness, but Lana encourages her, telling her to treat it as any other match. Arriving at the battlefield, they take their positions and send out their Pokémon: Primarina and Tsareena. From the stands, Ash and the rest of his classmates wish both of them luck. Olivia starts the battle, and Mallow makes the first move by ordering a Magical Leaf. Lana counters with Sparkling Aria, which not only stops Mallow's attack, but also attacks Tsareena at the same time. Unable to dodge the attack completely, Tsareena is hit, taking the first blow of the battle. Lillie says that Tsareena, who mostly specializes in close-range combat, isn't easily going to get close enough, but Rotom says that if she does get close enough, she will win.
Tsareena is forced to stay on the defensive as Lana continues her relentless assault. As another Sparkling Aria is fired, Mallow has Tsareena block it with Trop Kick, before charging in for a Stomp. However, Lana then surprises Mallow by having Primarina use Icy Wind, stopping Tsareena on her tracks. In the crowd, Mallow's classmates are also surprised to see that Lana has taught Primarina an Ice move in preparation of fighting against Grass types. Another Icy Wind blows Tsareena back, and she falls on her knees. Surprisingly, Mallow suddenly adones a peaceful look and compliments Lana, before taking out Tsareena's Poké Ball. However, when she tries to recall Tsareena, it doesn't work, and Tsareena forces herself back to her feet. Lana tells Mallow how she's always liked how considerate she is of others, but right now, Tsareena wants to keep fighting by her side. This makes Mallow remember the times she's shared with Tsareena, ever since she was a Bounsweet and a Steenee.
Her resolve renewed, Mallow puts Tsareena's Poké Ball away and declares that she will keep fighting to win by her side. As the two Pokémon start exchanging attacks again, Mallow understands that Tsareena can't take another blow, which means they must finish the battle with their next attack to have any hopes of winning. She insecurely looks at her Z-Ring, but looking at Tsareena, she is reassured. Tsareena walks up to her Trainer and the two embrace each other. Suddenly, Mallow's Grassium Z starts to glow, and Mallow feels the Z-Power flowing through her. She and Tsareena perform the Bloom Doom pose together, covering the whole battlefield in flowers. Lana is impressed, but refuses to lose, executing her own Z-Move, Oceanic Operetta, which she uses to block Mallow's Z-Move. For a few intense moments, the two Z-Moves clash, eventually cancelling each other out, causing the water from Lana's Z-Move to rain all over the battlefield. Lana orders an Aqua Jet, which Tsareena tries to counter with Trop Kick, but her exhaustion catches up to her, and she stumbles, resulting in the Aqua Jet hitting her dead on and causing her to faint. Moved to tears by the emotional battle, Olivia declares Lana the victor.
With the battle over, Lana walks up to Mallow, and the two compliment each other, sharing a grateful handshake. Waving for the cheering audience, Mallow expresses her happiness of having gone all out, as well as the frustration of losing. The rest of the group swears not to lose either, as the episode closes with the image of Mallow and Lana happily holding hands together.