It happened in a literal flash, as so many things did, when the Crystal Gems were around. Amethyst and Pearl had just returned from a mission of some kind - or Opal had, sagging slightly, as Steven ran over to her side.
“What happened?” There must have been a fight, and he missed it. Old excitement warred with newly-discovered worry, making his stomach grumble.
“Garnet, make a note,” Opal said, in a voice that sounded more like Pearl than Amethyst. “The temple in Peru is positively crawling with-” She spread out her arms. “Great big bugaboos, this big!” Okay, that sounded more like Amethyst. Opal’s form wobbled, breaking apart into smaller Gems.
“This would have gone much more smoothly, if you hadn’t insisted on wading into their midst, leaving your flank and your gem unprotected,” Pearl said with a huff. Amethyst was looking greener than usual, now that Steven thought about it, mottled and bruisy against her normal purple.
She rolled her eyes at Pearl’s tone. “Yeesh, I’m fine, Miss Prissy Pants!. We would still be there, with wormlons all down our throats, if we did it your way. Since Garnet wasn’t there for you to hide behind, and all.”
If looks could kill, Pearl’s glare would have at least put Amethyst in the emergency room.
“Long story short,” Garnet interrupted, getting between the two of them. “Did you get it?”
A bubble floated up from behind Pearl. “Naturally, and most importantly. We can deal with the wormlons at our leisure, now that the main threat is contained.”
“What is it?” Steven asked. The device inside the bubble looked like a fine wire mesh.
“It’s a cloaking device,” Pearl explained. “I’m sorry, Steven. I wasn’t trying to ignore you, when we first arrived. Merely…”
“We had other stuff.” Amethyst thumped down next to Steven, leaning against his side.
Steven poked gently at one of her bruises. “Hey, you want me to lick you or something?”
“Hehe, best power ever.” Amethyst grinned, surprisingly sharp for someone as round as her. “I betcha say that to all the girls.”
“If they’re hurt, yeah!” He spit on his hand and poked her again.
“There, all better!” Amethyst hopped back to her feet. “Imma go back there and take care of the rest of those nuggets.”
“We really should, but…” Pearl sounded uncertain. “It’s no good, leaving an enemy at our backs, so to speak.”
“I’ll come with you, this time.” Garnet’s voice brooked no argument. “Steven as well.”
Pearl frowned. “Are you sure about that?”
“He’s seen worse.”
“Yes, that’s why…”
The warp pad lit again, unexpectedly. Garnet didn’t hesitate, getting between Steven and the incoming danger, just like she’d placed herself between an arguing Pearl and Amethyst. Gauntlets flared around her clenched fists. Amethyst already had her whip out. Out the corner of his eye, Steven could see Pearl drawing her spear.
“No, it’s not possible, it’s too soon, how could she-?”
“It’s not Peridot,” Garnet said. At the base of the warp pad stood a slithery worm thing, almost as tall as Garnet.
“Okay…” Pearl frowned. “That definitely shouldn’t be possible.”
“But,” Steven bit his lip. “There must be a warp pad, where you found these guys, right?”
“Well, they shouldn’t be intelligent enough to use it!” but all Steven could think of was, they were Gems, once.
Amethyst cracked her whip, right as the wormlon moved off the warp pad. Wire and sinew wrapped tightly around its segmented body. Garnet moved in for a clean strike. The wormlon scree-d, as her gauntlets smashed into its head.
“See? No sweat!” Amethyst ran a free hand through her hair.
...And thereby jinxed the whole thing. With its last reserves of strength, the wormlon pulled out of her grip, and lunged for Pearl. She threw her spear, piercing the enemy, but not before it plowed into her. The bubbled artifact, which had been floating just above her head, popped, almost comically.
Slowly, regally, the wire mesh grew, and descended right on top of the Crystal Gems. Light flashed, blinding and painful. The last thing Steven heard was Pearl’s exclamation of “Oh, drat!” She sounded like she wanted to use a much ruder word, just then, he thought, and blacked out.
“Steven? Steven, I’m so sorry. I should never have been so careless.” Someone’s hand shook his shoulder. The voice talking to him was almost, almost familiar. He peeled his way out of the fog, opening his eyes.
The woman in front of him looked like Pearl, wore Pearl’s clothing. The differences, however, were difficult to ignore. Instead of its normal sheen, her skin was a dusky rose, like Mrs. Mahiya’s, from the pet store. Her hair was cut in the same pointy bob, only now it was black, with only the very tips retaining their peachy color. The shape of her nose had softened down, more like Amethyst’s, than its normal beaky shape.
“Oh, thank goodness! I thought you’d never wake up! I mean, of course you’d have woken up, what was I thinking? I could tell you were breathing, of course, and you didn’t lose your tendency to drool when you sleep.”
She frowned. “What is it? Are you hurt? Is there something I should be doing? Taking you to a hospital, perhaps? And of course there’s no warp pads there. I’ll have to get Greg to drive you.” Mild aggravation seeped into her voice.
“It’s not- I’m fine. But what happened to you?”
Pearl laughed nervously. “Oh, I’m fine, of course. Totally unhurt. That explosion must have done for the wormlon, though. I don’t see it anywhere.”
Someone groaned, and Pearl whirled around.
“That- Bwuh! That was no fun at all! Let’s never do that again, and say we did.” A decidedly un-purple hand reached out, tweaking Pearl’s nose. “Whoa, P. Did it bite off your schnoz?”
“I beg your pardon?” All color drained from Pearl’s face, as she took in the person addressing her.
If Pearl had looked a little different, Amethyst had changed an awful lot. She’d grown by like at least a foot, which Steven privately thought was super unfair. What she’d gained in height, she seemed to have sacrificed in hair, which only reached halfway down her back now, brown, with a single white streak. Her eyes, both visible now, had shrunk, slightly smaller and more petal-like than Steven’s own. Her body was still curvy and round; at least that was a relief.
“We have a problem on our hands.” Garnet, at least, looked refreshingly similar, her skin only a shade darker, eyes still hidden beneath her sunglasses.
“I’d say!” Pearl’s own hands shook.
Amethyst flopped onto her back. “Hey, Steven. We’re total imposters, come to steal your friends in the night and take their place. Whatcha gonna do about it?”
Fear welled up in Steven’s chest, sick and hot, making his lip tremble and his eyes spill over. “No, you’re not! Stop saying that!” It had to be them. It had to be. Something weird had just happened. That was all. Weird things always happened to them, so much that even Ronaldo didn’t care.
Garnet stooped to pick him up. He buried his face in her thick curls. “Of course it’s us. Oof, you’re heavier this way, aren’t you?” Her muscles still didn’t seem to be straining, at all, and her arms around him were very tight.
“It must be the cloaking device,” Pearl murmured. “It alters the composition of a Gem’s body, the better to blend on alien worlds. It was used for reconnaissance. We were worried Peridot might find it, which would in turn make it more difficult for us to find her, and easier for her to do all kinds of harm, so we thought it best to retrieve the blasted thing, from where it had been stored all these years.”
“So, it made you guys look human?”
Amethyst did a little twirl. “Ya like? We look just like you, now. Kinda boring, if you ask me. Could use more arms. Let’s say… three more arms.” Her face puckered up in concentration. “H-hey, what gives.” Amethyst’s eyes had gone wide and scared. “Why can’t I shapeshift?”
Pearl bit her lip. “That wasn’t supposed to be part of the equation. As the cloak was designed, the Gem would retain all of her abilities. The change would be merely cosmetic.” She turned to Garnet. “Try to make your weapon appear.”
Garnet put Steven down, and clenched her fists. Nothing happened. Steven could see her skin lighten with tension, around the knuckles.
No one spoke, for a moment, the silence only broken by Amethyst announcing, “this blows!”
Pearl sighed. "We should have just let Peridot have it. It would have solved a lot of our problems."