During the evening, Ashly is watching fireworks display with her friends as the fireworks display faces of Pikachu, Rowlet, Popplio and Litten as a colorful being watches the fireworks which end up with a great shining finale which amazes Ashly as she leans into Kiawe's side before a ball is thrown into the sky exploding like a firework, then reforms itself. The ball floats around shocking the heroes; Mallow thinks the firework event is not over yet, but Kiawe reads it should be done by now as the ball lands on the colorful being who performs tricks with the ball. The being goes to the heroes whose ball explodes and startles everyone. The being continues performing by exploding the ball and reforming it which amazes everyone as the being's ball explodes which causes an Ultra Wormhole to open causing an wired-like Ultra Beast to emerge out. The being kneels ending it's performance, then jumps away across the sea. Ashly is disappointed the performance ended, but the wired-like Ultra Beast as she thinks to herself really why Richard is here really.

The next day, the heroes comment on the performance the being made and wonder if it was an Ultra Beast, but just as Pikachu makes gestures of that being, the school bell rings and Kukui presses the button to let the heroes go to the base as Ultra Guardians. The heroes and their Pokémon change their outfits and go to the base where the monitor activates displaying Wicke, Lusamine and Burnet. Lusamine greets the Ultra Guardians and showing last night there was the colorful creature and analyzing it, Lusamine deduced it to be an Ultra Beast. Burnet adds they detected an Ultra Wormhole opened near the coast and are trying to figure out the exact location as Lana comments it really is a Pokémon while Lillie notes that Ultra Beast is a showoff which Lusamine has named it as Blacephalon; Rotom updates itself stating Blacephalon is a Fire/Ghost-type Pokémon who startles people with it's explosions to absorb their energy while they are surprised.

Suddenly, the lights go out which scares Sophocles as Togedemaru runs about and knocks Sophocles as she illuminates the room. Clefable activates the backup generator to power the place up. Lusamine shows the location to be Route 3 on Melemele Island and dispatches the Ultra Guardians away. The Ultra Guardians go on their Poké Ride Pokémon and fly away. Elsewhere, the wired-like Ultra Beast absorbs electricity from a substation as the Ultra Guardians reach the place noting that is not Blacephalon, but is another Ultra Beast. The Ultra Beast attacks nearly electrocuting the group who sees it is absorbing electricity to power it's attacks up making Ashly to wonder why Markus ia doing this really. Lusamine contacts Ashly as they also saw this new Ultra Beast as Burnet believes the explosions last night have opened the Ultra Wormhole while Wicke is concerned about the electricity drain as this is not a good thing really.

To prevent that fully really, Lusamine has Wicke contact the authorities to stop the distribution of electricity in that area. The Ultra Beast stops and becomes angry that there is no electricity left to absorb as Ashly and Sophocles go to have the Ultra Beast lured out by having Storm, Togedemaru and Charjabug emit electricity as the rest fully prepare Beast Balls to catch it, but however, Poipole floats around the Ultra Beast who tries to avoid it as Storm emits Thunderbolt, Charjabug emits Discharge and Togedemaru fires Zing-Zap, which draws the attention of the Ultra Beast. However, the Ultra Beast chases the Pokémon, while Kiawe, Lana, Mallow and Lillie fly near to the Ultra Beast. Just then, the ball appears and explodes, burning the group. The group realizes Blacephalon has arrived with a powered-up blast this time. The two Ultra Beasts face off against each other while Blacephalon's ball explodes to startle it's enemy as the other Ultra Beast continues to charge up.

The Ultra Guardians watch the confrontation as Lana fully believes they are having a Rumble Crash showdown as the Ultra Beast fires electricity at Blacephalon who evades and throws the ball to it's enemy who takes damage from the explosion as the Ultra Guardians throw the Beast Balls, but the explosions and electric crackles prevent the Ultra Beasts from being captured. The wired-like Ultra Beast emits electricity in a form of a whirlpool which fuses with Blacephalon's blasts and looks like a galaxy as Rotom records it. The Ultra Guardians are amazed, but Mallow reminds they have to do something about this as Lusamine contacts the group, telling the wired-like Ultra Beast has been dubbed as Xurkitree, an Electric-type Pokémon that creates shock waves. Lillie asks why are they having a confrontation as Lusamine believes they are trying to make a performance showdown to defeat one another making Ashly to worry as both shouldn't be doing this really.

She fears what could happen if these performances were to escalate even further and is why Burnet reminds the importance of sending them back home. Since the Beast Balls are repelled, Ashly believes they could fight them by performing, too as she believes if they can have their Pokémon perform shiny fireworks, they could gather the Ultra Beasts' attention. Ashly sends Lycanroc and Kiawe sends Turtonator while Mallow, Lana, Lillie and Sophocles count on Popplio, Steenee, Snowy and Charjabug, respectively. Storm shoots out an Electroweb while Togedemaru and Charjabug use Zing-Zap and Discharge which fuse with Electroweb and Popplio emits Bubble Beam and Steenee fires Magical Leaf which was followed with Charizard and Turtonator's Flamethrower, the Ultra Guardians have their Poké Ride Garchomp, Altaria and Flygon collide the form with Fire Blast making Ashly to have a flash back of this happening before in the past really.

Xurkitree and Blacephalon stop to watch the performance as Snowy uses Powder Snow as Poipole finishes by emitting sprinkles and impress Lusamine, Wicke and Burnet who watch the showdown. Blacephalon and Xurkitree attempt to make a greater performance and with the two distracted, Ashly presses the Z-Ring, passing the Z-Power onto Lycanroc, who uses Splintered Stormshards to greatly weaken the Ultra Beasts and Lana throws her Beast Ball as does Lillie whose ball is thrown off-course, but it is redirected by Steenee. The two Ultra Beasts are captured and the Ultra Guardians cheer for success as Lusamine, Wicke and Burnet see the children have grown a lot and are glad they resolved the situation. The next day, Koko watches as Burnet opens the Ultra Wormholes to have both Xurkitree and Blacephalon sent back to their home worlds. Back at school, Kukui explains the event venues have asked of the heroes to repeat their firework performance.

Everyone starts wondering if they could pull the trick once more until they hear Lana muttering how this is a good business opportunity as Ashly ACTUALLY had wrote it down during that time really making it easier to really remember it as she loves it fully actually really. Lillie, at her mansion, practices throwing as she switches her hand and with Snowy bumping the ball succeeds in hitting the target which Lillie is amazed and aims to continue training. Ashly remembers the flash back as SHE uses her Pokémon to do as many fireworks as she can like that and had Rock Throw be used to make them exploded making so many sparkles to come down as SHE makes sure there was different types and some in forms of Pokémon making many to love them as it's always during a festival really making Ashly to write down the moves for them and how to do it making her to wonder if she should tell them, but the truth will come out as she remembers the day the first Moon Priestess and Sun Priest had everyone praying to the 'Blinding One' really.

'I'll revel everything on that day then.'