It didn't take long for Rainbow Dash and Applejack to explain to Twilight about what had happened in the cottage, nor for the alicorn to tell them about the letter.
Once they were all caught up, Applejack asked aloud the question on all of their minds.
"So, what's next?"
Twilight stood in front of the unconscious changeling, making a mental note of its strange appearance. In other circumstances, she would have loved to study it and find out as much about changelings as she could. Equestria still knew practically nothing about changelings besides their abilities.
But even if this changeling was working alone, Twilight didn't see any possibility other than nefarious intent as motivation for impersonating Fluttershy.
Even after everything that had happened during her brother's wedding, Twilight had hoped that the next time she met changelings, it wouldn't be as enemies. That there would be room for negotiation and peace.
That they would be proven to be something other than enemies bent on destruction of Equestria.
Twilight sighed and shook her head, returning to the present. She had already formulated a plan that she saw as the most logical course of action to take in this situation.
"Rainbow Dash. The real Fluttershy should still be in the meeting. You can get to Smoky Mountains faster than anypony else. Find her and make sure she is safe."
The cyan pegasus nodded with a determined look on her face as Twilight turned towards Applejack next.
"Applejack, you stay here and guard the changeling. We can't just carry it out in the open. It would cause panic and alarm any other possible changelings in Ponyville."
The apple farmer nodded, turning her head to look at the changeling again and then around the room, hoping to find rope or something else to tie their prisoner with as Twilight finished.
"I will return to the castle and get my books. I'm sure I can find some spells that can contain the changeling and its magic, at least temporarily. That will give us time to come up with a more permanent solution."
Rainbow Dash didn't even wait for Twilight to finish her sentence before she exploded out of the cottage, turning up to take some altitude and then quickly disappearing into the sky as she started her long journey towards the distant mountains in the west.
Meanwhile, Applejack had found some rope from a closet and started tying together the changeling's legs and wings.
Twilight looked around the room one last time to make sure that she hadn't missed anything before turning around and walking towards the door.
But then, she realized that they were possibly against an unknown number of changelings with equally unknown plans and turned back to look at Applejack.
"Don't open the door for anypony else but me. This changeling might be working alone, but if it isn't..."
Twilight felt a shiver go up her spine at the thought of possibly anypony in the street being a changeling in disguise, watching, observing, waiting for an opportunity to take her away and wrap her in some slimy cocoon...
"How’ll I know it's really you? These things can look like anypony."
Applejack's question fortunately broke Twilight's reverie and after a moment of thought she nodded.
"You're right. We need something…like a password?"
The earth pony nodded as she tightened the last knot around the changeling's legs. "Sounds good to me. What’ll it be?"
That was a good question. It would need to be something only her friends would know.
Her thoughts returned back to the wedding in Canterlot when they had first seen the changelings, and she got an idea from there.
"When I come back, ask me what B.B.B.F.F means."
Applejack smiled and nodded again. That was certainly something only Twilight's friends and family would know about. "Will do."
Twilight returned her friend's smile with one of her own, a facade she hoped would hide the growing uncertainty she felt, and walked out of the cottage, closing the door behind her.
As she walked down the path, Twilight couldn't help but think that this couldn't have happened at a worse time. Rarity, Spike, and Starlight were all out of Ponyville. Without her dragon assistant, Twilight had no quick way to inform anypony about what was happening.
Hopefully she could at least find Pinkie Pie and…
Twilight was so deep in thought that she barely even noticed the mailpony who had delivered Fluttershy's letter to her earlier as they passed each other on the road.
The mailpony didn't slow his stride as the Princess of Friendship went past him, set on his path towards Fluttershy's cottage.
When she regained consciousness, Fluttershy couldn't remember where she was.
All she knew was that it felt like her head was about to burst. Sharp flashes of pain kept hammering her head as she groggily opened her eyes.
Black dots filled her vision as she tried to understand where she was. She was lying on a wooden floor. After a few seconds, she realized that she was in the living room of her own cottage.
Had she fainted? What had happened?
Her limbs felt sore and as she tried to move, she realized that she couldn't. Both her legs and wings refused to move, the latter tightly pressed against each other. Even her head felt heavy, like it had some extra weight on it.
Fluttershy started to panic, but then, at the edge of her vision, she saw somepony sitting in a chair next to her looking out of the window.
She smiled as she recognized who it was. There was no way of mistaking that hat for anypony else!
"Applejack!"
Fluttershy's words stuck to her throat as the apple farmer turned to look at her with a look that looked so angry and hostile, it made her want to cry.
"Don't even try. You ain't talkin' your way out of this one, changeling."
Fluttershy could only stare at Applejack, hearing her words but not really understanding what her friend was saying.
As Applejack turned to look out of the window again without saying another word, Fluttershy was left staring at her in shock, not understanding why her friend was acting like she was a…
...monster.
Very slowly, Fluttershy started remembering. At first she couldn't believe it, but then she turned her gaze up and saw the horn coming out of her forehead.
She stared at it for another moment before turning her head to look at her legs, fearful of what she would see.
As Fluttershy looked at herself, a tightness formed in her throat and she found it hard to breathe.
She shook her head in denial of what she saw, tears rolling down her cheeks.
This had to be a nightmare.
This couldn't really be happening.
But there was no denying it. No matter how much she stared at her limbs, black and filled with holes, they refused to turn back to what she knew they really looked like.
She was a monster.
Fluttershy let out a weak whimper, which then quickly turned to a sob.
The changeling known as Fluttershy cried, her entire body trembling, her wings pathetically twitching in their restraints as she tried to cover her face with them. When that didn't work, she just turned her face against the floor.
It was all Applejack could do to stare out of the window and keep her expression emotionless.
She knew this was an act. A cruel trick to fool her into feeling sympathy by using Fluttershy's voice and what little resemblance the changeling had left of her face.
Even so, it hurt Applejack's heart to ignore somepony crying in what all her instincts told was genuine sadness and despair.
It was probably because Applejack was trying so hard to ignore everything besides what she saw through the window that she failed to notice they were no longer alone together in the room.
Fluttershy felt something tap against her cheek. She turned her head and saw a squirrel, looking at her with sadness in its eyes, chirping at her, and asking why she was crying.
The changeling blinked as the cottage seemed to come alive with the movement of her friends.
Applejack stared with an open mouth as animals started appearing from the nooks and crannies around the room, some birds flying in from the outside to stand on the windowsill.
Fluttershy's sadness was overcome by surprise as she looked at all her animal friends. Applejack couldn't understand what they were saying, but she could.
None of them were commenting her appearance. They were all either asking why she was so sad or how they could help.
It took a moment for it to sink in.
All of them still saw her as Fluttershy.
She was still trying to process that when Applejack saw how one of the squirrels was staring at the ropes the apple farmer had tied around the changeling and moved to chew at them.
"Stop!"
The animals ran away as Applejack's hooves hit the wooden floor and the earth pony walked to Fluttershy.
"What in tarnation do you think you're doing?"
Applejack's hoof slammed down on the floor to drive away even the most stubborn animals from the changeling.
So, that had been its plan. Using Fluttershy's animals to escape. Was the changeling mind controlling the animals like Chrysalis had done to Shining Armor and Cadance's bridesmaids?
A bunch of critters couldn't hope to do anything to her, but Applejack wasn't about to start beating up small animals.
"Can't you see that this ain't Fluttershy?" She pointed her hoof at the changeling's horn, the transparent wings, and the black limbs. "I'm sorry, but this changeling ain't moving an inch until Twilight gets here."
Fluttershy blinked at the mention of the alicorn and then her eyes widened as she remembered properly what had happened just before she had fainted.
"Is Rainbow Dash alright?!"
Applejack looked down at the changeling, keeping her expression stern.
"Dash is alright and on her way to Fluttershy right now." The apple farmer poked the changeling's chest with her hoof. "So, you can drop the act, ain't nopony here for you to fool."
The apple farmer turned to look around the room at the animals, who were keeping some distance away, but refusing to leave entirely, before she turned to look at the changeling again.
"I'm sorry, but if you don't stop trying to make these animals to do your dirty work, I'm going to knock you out."
Just to emphasize her point, Applejack pressed her hoof against the wooden floor hard enough for it to crack, making a mental reminder for herself to fix the floor and apologize to Fluttershy when this whole mess was over.
"And I'll do the same if you try any other tricks too."
Fluttershy first looked at Applejack's uncompromising expression and then at her friends. She didn't need even think about what to do.
The changeling shook her head to all the animals in the room, saying aloud. "I'm alright, you don't need to worry about me."
Reluctantly, the animals left the room, leaving the pony and the changeling alone with each other again.
Applejack turned away and returned to her chair, but Fluttershy was no longer crying. She felt newfound strength inside herself and dared to hope that she had found a way out of this nightmare.
She was still Fluttershy. Her animal friends had known that. They didn't care how she looked.
And she knew that she was Fluttershy. Nothing else mattered, right?
All she needed to do was to convince her friends of it as well.
"Applejack, please listen to me."
The apple farmer sighed and turned to look at the changeling again, who awkwardly wiped her tears away before looking at Applejack and sitting up as much as she could with her legs tied together.
Applejack stared into those yellow eyes and despite herself, she was taken aback by how determined the changeling suddenly looked. The apple farmer didn't say anything, waiting for the changeling to say whatever it was going to.
Fluttershy took a deep breath and then started to speak.
"When we went to stop the Nightmare Moon, the manticore we met in the forest had a splinter stuck in its paw. When we met Zecora for the first time and thought she cursed us, you became tiny and my voice changed."
Her friend kept staring at her with the same guarded expression, but Fluttershy could tell that Applejack was looking a bit less certain about herself now.
At least, that was what Fluttershy wanted to believe as she continued.
"Pinkie Pie has a secret cellar where she plans her parties. I was the one who got out first when we were prisoners in Starlight's town."
This went on for a few minutes, Applejack's expression gradually changing from stern determination to puzzlement. She was still suspicious, but this changeling was unnervingly well informed.
Finally, the apple farmer waved her hoof at the changeling to make her stop.
"Alright. You know things, I’ll give you that much, but I still ain't buying any of this. My friend is no changeling and she would never try to blast Rainbow Dash through a wall."
Before Fluttershy could answer, Applejack continued, growing more determined with each word.
"We have the letter from the real Fluttershy too."
After blinking in surprise, Fluttershy frowned at the mention of the letter, not knowing what her friend was talking about.
Unfortunately, Applejack interpreted that as her having found something the changeling couldn't explain away.
"Didn't know about that, did you? So good try, but you ain't fooling me."
Fluttershy felt her heart sink, but tried to calm herself down. She didn't know anything about any letter, so she couldn't explain it. She just had to stick with the truth and hope for the best, that was her only option.
"Applejack, I swear I didn't send a letter! I don't know why I look like..." Fluttershy looked at herself and then at her friend, "...like this! It must be some sort of spell! Please believe me!"
The apple farmer was silent for a moment and then sighed. "If… if you really were Fluttershy and believed that, then you must know that best you can do is to wait for Twilight, right? If it's a spell, she’ll figure it out."
Fluttershy sighed in relief, happy that she had at least made some process. And Applejack was right. So she just nodded. "Yes, I know. I'm not going to try to escape, don't worry."
Applejack looked at the changeling for a moment longer and then sighed, shaking her head.
“It’s not like you could escape even if you tried.”
The Element of Honesty wasn't sure what she thought anymore. For a moment there, she had almost believed the changeling.
She couldn't deny that the best way this could turn out was if this was just a spell somehow accidentally cast on Fluttershy while she was at the meeting.
So, Applejack felt no shame in sincerely hoping that was the case and that this changeling that looked like Fluttershy was the real Fluttershy she knew, just with some magical makeup.
And that there were no real changelings involved in any way.
That hope was almost immediately dashed when the cottage's door was suddenly blasted off its hinges in a flash of green fire and dozens of changelings charged into the room, heading straight towards Applejack.