Later, after lunch, Sunset and the Humane 5 were walking through the foyer while Pinkie skipped.
"Those three are definitely in possession of some kind of dark magic." Sunset speculated about Adagio and her friends believing that they may have Equestrian magic. "How else would you explain what happened there?"
"Don't worry, y'all. We'll let Principal Celestia know all about this and those girls will be kicked to the curb in no time." Applejack reassured. "Last thing she needs is another CHS event almost ruined by some power-crazed lunatic." Applejack then realized the last part she said and turned to Sunset. "Uh, no offense."
Sunset sighed at Applejack's comment. "None taken."
Later when the girls arrived at Principal Celestia's office, they informed her and Vice Principal Luna all about the Dazzlings.
"Dark magic? I find that hard to believe." Principal Celestia said to Sunset doubtful of her claims while peering through the blinds at her window. When she saw the coast was clear, Celestia returned to her desk and sat down. "Those girls came into my office earlier and were absolutely delightful."
Luna scoffed. "Perhaps Sunset Shimmer is just eager to make someone else a bad element. So, that her actions at the Fall Formal would become old news."
"I can see why you'd think that. But--" Sunset tried to say before Rainbow unintendedly cut her off and went in front of her.
"That's not what's happening." Rainbow explained. "We saw all this go down at the cafeteria, too."
"Yes, but isn't your band supposed to be part of the Music Showcase?"
"Yes?" Rainbow Dash answered awkwardly after pausing for a moment.
"Perhaps you're all just worried that the Dazzlings will steal your spotlight." Luna once again accused the group.
"The Dazzlings?" Applejack asked.
"It's the name of their musical group." Celestia soon explained. "That's why they came by my office earlier to sign up for the showcase. Even sang a little song to Vice Principal Luna and I." Sunset and the Humane 5 developed looks of confusion and concern over what Celestia was talking about.
"They did?" Applejack asked again.
"Yes. And we think having a Battle of the Bands is a marveous idea." Celestia further explained. It was at that moment that Sunset and the Humane 5 saw the green aura in both Celestia and Luna's eyes, realizing that they were now under the Dazzlings' control and that they were out of luck.
The girls then hung out by the statue on school campus.
"I can't believe they got to Principal Celestia and Vice Prinpical Luna, too." Fluttershy fretted worrying for her school's principal and vice principal.
"They've gotten to everybody!" Rainbow Dash stated trying to balance a soccer ball on her head.
"Not everybody!" Pinkie sang referring to themselves.
"Pinkie Pie is right." Applejack said agreeing with Pinkie. "We were there when the Dazzlings were singing, but we weren't affected. It was like we were protected somehow."
"So, let's take them down!" Rainbow said. "I mean, it's not like we haven't tangled with dark magic before and totally whupped its sorry butt!" Rainbow realized what she said. "Uh. No offense."
Sunset scoffed and rolled her eyes. "Non taken. Again." She was getting clearly annoyed by everyone doing that in front of her, even when she knew they didn't mean it.
"That was when Twilight was here." Fluttershy pointed out as the ladybug flew off her finger and she watched it fly away. "There maybe some kind of magic inside us. But it only comes out when we play music. I sure don't know how to use it to...whoop anybody's butt."
"If only we can get a message to Twlight." Rarity sighed thinking of a solution to their current situation while polishing her nails. "Maybe she can tell us how to break the spell the Dazzlings have cast on our friends."
"Well, that's not gonna happen. The portal's closed." Rainbow reminded her tossing her soccer ball at where the portal to Equestria was, where it bounced off above Rarity's head. Rarity ducked her head, causing her to spill some of her nail polish on her arm, much to her chagrin.
"And I get the feeling the don't exactly have cellphones where she's from." Rainbow then theorized about how Equestria works after catching her ball.
Sunset began to think for a moment until she came up with an idea.
"I may have an idea how we can get in touch with Princess Twilight." Sunset told the Humane 5.
She brought them to her locker back inside the school, where she took out a book and showed it to them. It was a basic brown book and had a thin layer of dust on the cover.
"When I was Queen Celestia's student back in Equestria, she gave me this." Sunset told the Humane 5 wiping some of the dust off the cover of the book, which revealed to have her cutie mark. "Even after I abandoned my studies, I held onto it. Deep down, I guess I knew I was making a big mistake. And I wanted to still have a way to reach out to her." Sunset opened the book and flipped through a couple of filled pages until she came across two that her blank. "Maybe it still works."
"That's a book, Darling." Rarity said to Sunset. "What do you mean 'maybe it still works'?"
"It used to be that if I wrote something here, it would appear in the pages of a book back in Queen Celestia's library." Sunset explained to Rarity. "I get a message to her, then she get a message to Princess Twilight."
"So, what are you waiting for?" Rainbow asked handing her a pen to write. "Get to writing!"
Sunset took the pen and looked at it.
"Been a long time since I've written these words." Sunset said nervously as she began to write the words, "Dear Queen Celestia..."
The mysterious hooded figure watched this on his monitors in his lair and turned his attention to the spider bot stationed at Canterlot in Equestria. The spider bot scurried to the city's library and once inside began to analyze every book on each shelf for the one that was connected to Sunset's.
"Excuse me, Princess. Where do you want all these books from Celestia?" The hooded man then heard someone ask Twilight and turned his attention to the monitor of the spider bot that was stationed at Twilight's Castle. Twilight and the rest of the Mane 6 were in the middle of cleaning up the castle after their party had ended hours ago. The Mane 6 were cleaning the throne room where the party took place; Rarity was wiping off any stains of cake or punch she would come across, Applejack and Fluttershy were sweeping up the confetti off the floor, and Pinkie...well, she was collecting all of the still inflated balloons.
"The Library." Twilight answered to a delivery stallion, who was pulling a wagon containing stacks of books from her old library back at Canterlot. "Third door on the left."
The delivery stallion soon heard a rumbling sound coming from on top of the book stack. "Even this one that's glowing and vibrating?"
Twilight soon looked up to the same book the delivery stallion was referring to. This immediately caught her attention, along with Spike and the rest of the Mane 6, as she picked up the book with her magic and flipped through its contents until stopping at a particular page.
"What is it, Twilight?" Fluttershy asked Twilight.
"It looks like...a message to Queen Celestia from my friends at Canterlot High." Twilight answered analyzing what was on the page as the rest of the Mane 6 gathered around her.
"How is that even possible?" Rarity asked the same question everypony else was thinking.
"I have no idea, but...it sounds like they need my help." Twilight speculated as she then led Spike and her friends to the castle's library, along with the spider bot that followed them there through the ceiling. Once there, Twilight pulled out a book from the middle shelf. "The way Sunset described them, I think these new girls sound an awful lot like... *places the book down on the table* ...the Sirens."
"Not the Sirens!" Pinkie fretted before whispering to Fluttershy, "I don't actually know what that is"
As Twilight opened the book and explained to her friends about the story of the Sirens, the spider bot zoomed in its lense to the page Twilight was on, where it showed illustrations of the Sirens in their original forms. "The Sirens were three beautiful, but dangerous creatures, who had the power to charm ponies with their music. But to maintain this power, they had to feed on the negativity and trust of others. The more of this negative energy they consume, the stronger their voices became. And the farther they could spread their dark magic."
"I don't think I like this story very much." Fluttershy said already feeling uneasy about the Sirens.
"If the Sirens had their way, they would've divided and conquered all of Equestria." Twilight continued before turning the page showing an illustration of Starswirl the Bearded, along with the Pillars of Old Equestria, at his side banishing the Sirens into a vortex. "But a certain Starswirl the Bearded wasn't having it. Rumor has it, he found a way to banish them to another world. One he believed their magic power would be lost. That world must've been the one my Canterlot High friends live."
"But Starswirl must've sent them there ages ago. How come they're just surfacing now?" Applejack asked.
"I don't know." Twilight answered unsure, "But If my hunch is right, and it is the Sirens who've come to Canterlot High,this spell they've cast is just the beginning." Twilight closed the book, having gotten all the information she needed, along with the spider bot from above the library's ceiling. "My friends need me. I have to get back to them."
Twilight was about to leave until being stopped by Rainbow Dash, who flew up from and over the table and descended in front of Twilight.
"I hate to burst your bubble, Twilight, but the connection their world and Equestria will still be totally cut off for a super long time." Rainbow then reminded Twilight.
"Okay, first of all, if there was bubble blowing going on, why wasn't I told about it?" Pinkie then cartoonishly zoomed over to Twilight and Rainbow and asked, "And second, if the connection is totally cut off, how was Sunset Shimmer able to get a message to Twilight?"
Pinkie's question then gave Twilight an idea and she ran off. "Pinkie, you're a genius."
"Yeah. I get that a lot." Pinkie thanked Twilight before asking Rainbow, "Now about those bubbles."
Twilight teleported back into the library, this time with the Crystal Mirror from the Crystal Empire, as well as a couple of mechanical parts needed for her plan using her magic. Her friends were surprised that she managed to convince Cadance to give the mirror to her, but still wondered how she was going to get it to work. Twilight then began working on something offscreen and after some time passed, we see that she had converted the mirror into a dimensional portal device with the parts she acquired.
"...And the interval between the two points is defined as the square root of the sum of the squares of the separation between the points along three spatial dimensions." Twilight informed her friends about her update to the mirror, though this only confused them as they all looked at her in confusion.
"Say what now?" Spike asked trying to contemplate Twilight's words.
"Duh. She's going to take the magic in here. *points to the book* And put it in there. *points to the mirror* That'll make the portal open up so that whenever she wants to, she can go from here to there." Pinkie then explained simplifying Twilight's plan as she did a cartwheel before getting a bit carried away with the explaining, "There to here. Here to there. There to here. Here to there. There to--"
"We get the idea." Applejack then spoke up and assured Pinkie, who then politely trotted away from the mirror.
"Now to see if it actually works." Twilight speculated stepping over to the mirror and then taking and placing the book at a pedestal on top of the mirror, which soon powered up the machinery around the mirror. The others were awestruck at the process of the magic from the book being transferred into the mirror, ending it with an awe when the gateway between worlds was now open.
"Don't suppose we could join you this time around?" Applejack asked wanting to come with her along with the others.
"Better not." Twilight suggested, "It could make things pretty confusing if Canterlot High all of a sudden had two of all of you."
The rest of the Mane 6 all looked at each other for a moment and realized that she had a point, deciding to take her words to heart.
"Which reminds me." Twilight said before teleporting out of the library. After a few minutes, she teleported back now wearing her Fall Formal outfit.
"Why are you wearing the dress you came back in last time?" Rarity asked Twilight confused about why she was bringing the dress she brought with her from the other world last time.
"You know how we ponies don't normally wear clothes? Well, my Canterlot High friends told me that clothes are important to have at all times in their world. So, I don't want to greet them without anything on." Twilight informed Rarity, to which the rest of the Mane 6 nodded and saw that she may've had a point, considering she was the one who went there.
"But I still get to go, right?" Spike asked, "There isn't another one of me at Canterlot High. And you never know when you might need your trusty assistant."
"Mm-hmm." Twilight agreed granting Spike permission to go and then going over to the Mane 6.
"Yes!" Spike exclaimed happy to go.
"We won't be gone long." Twilight assured her friends as she and her friends embraced in a hug.
After that, she went back to Twilight at the mirror.
"Ready, Spike?" Twilight asked Spike.
Spike then got himself ready before answering to Twilight. "Ready."
The two prepared themselves as if they were about to start a race. And much like one, they dashed off into the portal to travel back to the world of Canterlot High. The mysterious hooded man then transitioned back to the screen connected to the spider bot that was monitoring the Humane 6, who were outside the school waiting for Twilight to come out through the bottom of the statue while it had transformed back into a security camera and perched itself at the top of the school's entrance. Rarity was polishing Fluttershy's nails, Sunset was looking through her book while sitting next to the statue whilst Rainbow Dash was doing tricks with her soccer ball, and Applejack and Pinkie were on top of the statue playing cards, to which the latter won, to Applejack's confusion.
Rainbow sighed. "I'm starting to think she's not coming--"
At the nick of time, Twilight and Spike emerged out of the portal dashing at high speed until they tripped tumbled to the ground.
"Twilight!" The Humane 6 exclaimed at Twilight's arrival happy to see her again.
"I'm back." Twilight nervously greeted her human friends. Despite her nervous reaction, she was happy to see them all again after all this time.
Sunset Shimmer came over to her side and offered her hand. Twilight appreciated Sunset's help as she took her hand and got back up. The Humane 6 then all swarmed around Twilight and hugged her, happy to see her again after so long.
"And I've got some bad news about those new girls." Twilight informed her friends in a more serious tone.