“Changeling!” yelled Applebloom, as she charged through the portal.
“Changeling changeling changeling!” yelled Sweetie Belle and Scootaloo, as they followed along.
* * *
And, for the first time since Twilight had set up her alarm spell, someone crossed it, heading out of the portal. The alarm spell buzzed and, in the upper room above the library, Twilight abruptly fell out of bed.
“Gh- wha-”
Twilight staggered to her hooves.
“Alarm spell! Portal!” she cried out, realising with commendable speed what the irritatingly persistent buzzing in her head meant. She took a moment to grab the checklist that she'd left next to her bed last night for just this eventuality, and vanished with a *pop*.
* * *
“Changeling chan-” *pop* *thump*
Applebloom looked up to see what she had run into, and saw a somewhat grumpy-looking purple alicorn.
Twilight sighed. “I really should have guessed.” she said. “What's it this time, Cutie Mark Crusader Archway Architects?”
“Changelings!” said Applebloom. “There was a changeling on the other side of that archway!”
Twilight hesitated. “...are you sure?” she finally asked.
“She said her magic is powered by love!” volunteered Scootaloo, hopping from hoof to hoof.
“And she did a double stop on a set of panpipes!” added Sweetie Belle.
“O...kay.” said Twilight. This situation was not covered by her checklist. With some reluctance, she teleported it back to the library. “So. A changeling disguised as a unicorn?”
“No, no, no, something else.” said Scootaloo.
“A – 'human'” said Applebloom. “That's what she called it, anyhow.”
“Kind of like a monkey, only with no tail and all its fur on top of its head.” volunteered Sweetie Belle. “And clothes that would make my sister run away screaming about fashion.”
“A monkey?” asked Twilight. “With clothes? And able to do magic? ...how odd. So. Did you see her do anything that proved she was a changeling? Any shapechanging? Any flashes of green magic?”
“Well... no...” admitted Applebloom.
“I never saw the colour of her magic at all.” said Sweetie Belle.
Twilight sighed. “Alright, so this is probably just a misunderstanding. No-one's left the portal except for you three, so at least we aren't facing a ravaging army of changelings.”
Sweetie Belle gasped. “What if one of us is a changeling!”
Applebloom gasped in shock. “It's gotta be Scootaloo!”
“What? Why me?”
“Ah know it's not me, an' if it was Sweetie Belle she would'na mentioned it.”
Twilight sighed, again. Her horn glowed, and each filly floated into the air, encased in a separate magenta bubble. “I'm pretty sure that none of you are changelings,” she said, “but in a case like this, it's better to be safe than sorry.”
* * *
Applejack was no happier than Twilight to be woken up at two in the morning.
“So.” she said. “Yer sayin' ma sister's been sneakin' out at night, an' now there's a teeny tiny chance that she's been replaced by a Changelin'?”
“Yes.” nodded Twilight. Two magenta bubbles floated behind her; Applebloom, in the third one, floated nest to Twilight's head. “And if so, it would have been recent, since our picnic yesterday. So if you could just ask her something that she'd know from before then...”
Applejack sighed. “Alright, sugarcube, what did we have fer breakfast yesterday?”
“Apple fritters.” replied Applebloom.
“A'right, that's ma Applebloom. Now, could ya put 'er down, Twi? Ah got to have a word with 'er about sneakin' off at night.”
Applebloom's face fell.
* * *
Rarity was, if anything, even less happy to be woken up at two in the morning than Applejack had been. She was particularly unhappy to be woken up by an alicorn teleporting into her room and seeing her mane before it had been brushed, and she would have been quite happy to spend several minutes describing in great detail precisely how unhappy she was about the situation.
Unfortunately, before she could get a proper head of steam under her rant, Twilight headed her off. “There's a teeny tiny chance that Sweetie Belle might have been replaced by a changeling, since our picnic yesterday. Could you ask her something that only she'd know?”
“Oh, very well, dear.” Rarity considered for a few moments, and then asked “Um... which hat did I wear... last Tuesday?”
“What?” asked Sweetie Belle. “How would I know that? I can't even remember which hat you wore yesterday, never mind last Tuesday!”
“Oh, come on, Sweetie, you specifically commented on it.”
“Oh. Um. The... yellow one? That looked like a lemon?”
“No, that was Thursday. Hmmm. Perhaps I should consider a different question... oh, I know! Sisterhooves Social. Where did we meet?”
“At the mud pit! You were hiding in there, and I thought you were Applejack, and...”
“Oh, I'd been neglecting you terribly!” continued Rarity, hugging the magenta bubble that held her sister. “And I've been doing it again, haven't I? Ever since that big order came through from Fancy Pants... and then the copycat orders from Jet Set... and Upper Crust...”
“You haven't been ignoring me at all!” cried Sweetie Belle. “Even when you're really busy, you spent lotsa time talking to me!”
“Yeah... I think we can be pretty sure she's not a changeling.” said Twilight, as she released Sweetie Belle from her bubble.
* * *
“A tiny chance that my daughter is a changeling?” asked the burly blue pegasus.
“Yes, Mr. Blue Rain.” said Twilight, nervously. Scootaloo's father, the leader of the weather patrol's night shift, was an intimidatingly muscular pony.
“Well, then. Scoots! Nine-seven-five.”
“Um... oh-two-four?” said Scootaloo, nervously.
Blue Rain frowned at his daughter.
“Oh!” said Scootaloo. “Right. Um... three-eight-seven?”
“Five-oh-one.” replied Blue Rain, promptly. “Alright, Miss Sparkle, she's not a changeling.”
“Um... what was that?” asked Twilight.
Blue Rain shrugged. “Family protocol.” he said. “We worked it out after hearing about that wedding in Canterlot. For obvious reasons, the fewer people who know exactly how it works, the better. I'd rather appreciate it if you didn't tell anyone else about it, Your Highness. But it does work, and that's certainly the genuine Scootaloo.”
“...right. If you say so.” Twilight dissolved the final bubble, allowing Scootaloo to drop meekly to the ground. “If you don't mind, I'd like to get back to sleep. Busy day tomorrow.”
* * *
In another world, the Great and Powerful Trixie woke up early. She'd parked her cart next to the first road she'd found; her internal alarm clock always got her up in plenty of time to get into the nearest city and set up before ponies started their day, in order to get the early crowd.
The only trouble was, she wasn't sure whether to proceed left or right along the road.
As it happened, she chose the wrong direction.