Getting the access code for Stockman's lab is easy enough. Bradford doesn't have a good memory for this sort of thing, so all Karai has to do is wait until he's training with the lower-ranking ninja before she breaks into his room and finds the piece of paper where he wrote it down.
No, the problem is going to be hauling out the large quantities of mutagen April says they'll need. Stockman can hardly help but notice the absence afterward; they're just going to have to cover their tracks as best they can and work quickly. It was even hard to choose a time when Stockman won't be in the lab, since he sleeps and eats there, too. However, he leaves every few days to scavenge supplies and visit his old workshop. Karai discovered this when she was assigned to follow him, right after she was reinstated. It was a boring evening, tracking the flying mutant while he muttered to himself in buzzing tones that no one else could make out, but it makes her hope that he'll be gone for a few hours.
Tonight's the night. Once she's sure Stockman's gone, Karai sends a surreptitious text to the others and slips down to the lab as soon as she can get away unnoticed. Keeping her hands gloved, she taps in the access code to the lock and ghosts into the lab, sticking to the shadows as she works her way around the room. It's a mess, cluttered with the detritus of Stockman's experiments. He's never been tidy, as far as Karai can tell, and it's gotten worse since he was mutated, especially since he's none too picky about what he eats. Karai holds her breath as she passes one of the smelly piles Stockman favors these days.
Fortunately, she doesn't have to search for anything small; the mutagen is easy to find, stored in large sealed drums against the far wall. Karai locates them first, to make sure Stockman hasn't moved or used up the supply, and then goes out to make sure the way to the loading dock is secure. As far as she knows, the clan isn't expecting any deliveries tonight, and sure enough, the storage area is quiet and unoccupied and the outer door is locked.
And Raphael is waiting outside when she opens the door.
Karai looks around wildly. "You were supposed to come with the van," she hisses.
"Casey and April are bringing it up," he says. "I've been here for an hour already. Just in case."
"Just in case of what? No one's supposed to see you, you idiot."
"No one's going to see me." He follows her inside. "Ninja, remember?"
Karai wrinkles her nose in annoyance. "We're ninja, too. We're not like your little human friends. We know what to look for."
"Yeah, well, no one even knows I'm back, right?" A heavy hand falls on her shoulder. Karai looks back, scowling, to find him staring her down. "Because you didn't sell us out, did you?"
She shrugs off his arm. "Oh, I get it, you still don't trust me."
"Give me one good reason I should."
"How about, I'm all you've got?" Karai snaps.
His eyes narrow and he bares his teeth at her. She turns her back deliberately, continuing to lead the way back to Stockman's lab. If he wants to attack her from behind, he can, but she doesn't think he'll do it. There's too much on the line for him.
And, in fact, he falls in behind her with no more comment. They make their silent way back to the lab, and that's where he speaks next. "So... are my brothers okay?"
She throws him a startled glance. "They're fine." The last time she checked on them, they were sleeping in a pile, so tangled up she could hardly tell one from another. "They're just, you know, doing snake things."
Raphael nods, jaw tight. "I want to see them."
"That's not part of the plan," Karai says, suppressing a sigh.
"I'm already here."
"To get to my quarters, you'll have to go through parts of the building where people are," she points out. "There's too much risk someone would see you."
"I want to know they're okay."
"I just told you!" Karai snaps.
He glares at her, almost growling, and Karai rolls her eyes and turns away. "Fine, do what you want. If you get caught again, don't expect me to bail you out." She stalks over to the closest mutagen tank and checks to make sure it's secured and not leaking.
She keeps her back turned resolutely, and after a moment, Raphael says, "That's it? You're not going to argue with me any more?"
"That ever stopped you from doing what you wanted?" She glances over her shoulder. "Look, I know my word isn't worth much to you, but I give it to you anyway. They're as healthy as I can get them. You were fine, weren't you? And it'll only be a few more days if we can just get this mutagen crap out of here."
He's frowning, narrow-eyed, but finally he gives her a reluctant nod, and together they maneuver the drum of mutagen onto a dolly and slip back toward the loading dock. Karai goes first, sticking to shadows and scouting out the way, letting Raphael haul the container. He's stronger than she is, anyway. Might as well put the extra muscle to use.
This time April and Casey are waiting in the turtles' ridiculous van. Karai really wishes they'd managed to steal something less conspicuous. "This enough?" she asks April as Raphael and Jones shove the mutagen into the van.
The other girl bites her lip. "I'd feel better if we could get more. Do you think we could manage one more tank?"
"Better hurry," Karai mutters.
April comes along; in her current black get-up, she could almost pass for a Foot ninja herself. One more tank, one more trip to the loading dock—
Of course, that's when Stockman comes back.
In spite of their training, none of them sees him coming. He swoops in from somewhere in the ceiling, hissing furiously. It takes Karai a moment to make out his words: "S-s-s-stealing my mutagen!"
Raphael, weapons already in hand, takes a swipe at Stockman, which he dodges, chittering. He's not as strong as most of the mutants, but his ability to fly gives him an advantage that's hard to beat. "Wait!" Karai cries, throwing up a hand. "Stockman, wait. Think about it."
Stockman hovers in mid-air, buzzing to himself. If Xever's face is hard to read these days, Stockman's is indecipherable. She can't even tell where the giant compound eyes are looking, but she can tell that he's noticed what she wants him to see when he says, "Turtle. Here, not s-s-snake."
"That's right," Karai says, still wary, but he seems willing to cease attacking for now. "There's a way to reverse the mutation, Stockman."
"If you let us take the mutagen, maybe we can help you," April says, picking up Karai's cue.
"Baxter S-Stockman doesn't need your help." Stockman zips toward her. April draws her own weapon, and Raphael growls and readies to spring.
"Don't you? We can make retro-mutagen," April says. "It's up to you whether we make any for you."
Stockman snarls at her, pulling back, and Karai adds smoothly, "Everyone knows you're an expert in robotics, not genetics."
"It's a fair trade," April suggests. "Let us take this, and you can have your life back."
Karai waits, ready to act, while Stockman hovers, staring at them, until he finally says, "Go. Take it. I'll keep s-s-s-silent."
#
It takes three days for April and Irma to make the retro-mutagen.
Karai spends those three days on pins and needles, trying to look normal, hoping that Stockman won't let anything slip, that Xever hasn't put too many pieces together, that Bradford and Tiger Claw won't get a whiff of what's going on. She trains and runs her patrols, stands guard over the weapons shipments. She has tea with Shredder, quiet and ceremonial, playing the part of the dutiful daughter.
She wonders if he has always only been playing the part of her father.
When they have drunk their tea, he tells her that they will be returning to Tokyo in a week's time. Karai bows her head and says, "Yes, father." Once she would have been glad to return to her old home, to familiar ground. But that was before. Too much has happened. When she lived in Tokyo, she was Oroku Saki's daughter.
Now, she is no one's.
She had thought removing one snake from the tank was difficult, but removing the remaining three is ten times worse. They resist being separated; they twine together and bite at her and hiss so loudly she whispers, desperately, "Quiet! Someone will hear you!"
By all rights, they shouldn't understand her, but she thinks they subside a little, watching her with slitted, unreadable eyes. She is forced to put them all into the same container, which she slings over her shoulder before stealing into the air vents one more time. Now she just has to hope that no one will check on her quarters and notice that the snakes' tank is empty.
Raphael meets her on the roof, one building over, a silent bulk sliding out of the shadow. He holds out his hand, and she hands over the container, and for him the snakes relax, loosening their coils. When he reaches in, they do not hiss or bite, and one snake attempts to wind its way around his arm. He murmurs something Karai doesn't hear as he closes up the container, and together they make their way down to the turtles' lair.
Karai fidgets while the others get things ready, barely acknowledging her presence. After what happened with Raphael, this time she'll keep her distance as the snakes transform. So she waits, trying not to do anything obvious like drum her fingers on her arm or rub her palms against her thighs. Soon they'll be back, and then she has an offer to make them. It's more than fair, but she doesn't know what they'll think of it, doesn't know what they'll be ready for. She doesn't know if she can do it on her own.
Karai crosses her arms and tries to look stern while Raphael gets the snakes settled and April gets the retro-mutagen ready. After a brief debate, it looks like they've decided to do all three snakes at once, though it takes some effort for Raphael to keep the three of them separated. April sprays the substance over them and Karai bites the inside of her lip, waiting.
After seeing the transformation once, it ought to seem normal, but it still looks... all wrong. The snakes writhe and twist, bones breaking and splitting as limbs spread out of their bodies, as skin thickens and re-shapes. They make harsh noises that modulate into guttural groans. It's surreal, it looks like something out of a movie, some triumph of special effects, but it's happening right in front of her, and when it's over there are three turtles crouched on hands and knees, panting.
Karai's hands curl into fists. April is biting her lip, body tense, almost bouncing on her feet. Irma fiddles with her glasses, and Casey just stares, until Raphael clears his throat and says, nervously, "Guys?"
One of them says, "Raph?" and then there's a scramble that ends up with all four of the brothers on their knees, arms around each other in a small, tight circle, all of them talking at once so urgently she can only pick odds and ends out of the babble. Karai presses her lips together and waits, feeling suddenly out of place, wondering if they'll agree to what she has to say.
#
April has to hold back from launching herself into the middle of the ring. They're here. They're okay. She did it—well, she and Irma, with help from Casey and Karai—but she brought them back. She has them again, and it's the smallest bit of repayment for all they've done for her. The only thing that dampens her sense of elation is the thought of Splinter. She knows what it's like to lose a father, but she always had the hope of getting hers back—because of Donnie and his brothers—and they'll never have theirs again, and Splinter must have died not knowing if his sons would ever be safe, would be themselves, again.
Maybe they feel it, too, because the excited chatter dies down into quiet, though the four brothers still keep hold of each other. Now April ventures forward, smiling hopefully, and as the turtles straighten up she says, "Hey, guys."
"April!" Donnie turns around at once, lighting up into a familiar smile when he sees her. He looks disconcertingly naked without his mask and gear, but he looks so happy for a moment that it's easy for April to overlook it and dash forward for a hug, which Donnie willingly gives. It feels just right, familiar and sure and safe, and her heart is nearly overflowing when she says, "I was so worried I wouldn't be able to get you back."
"But you did," Donnie says, and then Mikey piles onto the hug, unable to hold himself back any more.
April has to hug each of them then, individually and together, even Raph all over again. Casey even gets into it when Mikey tackle-hugs him, too. April's laughing when she finally disentangles herself, reluctantly. She says, "I wouldn't have been able to do it without your notes, Donnie. Or without Irma." She gestures toward her friend, who waves back with a nervous smile from where she stands near Casey. "And... and Karai helped a lot, with materials, and..." She trails off as all three turtles seem to realize for the first time that Karai is here.
Leo takes a step toward her and says, "Are you all right?"
Raph rolls his eyes, while Donnie and Mikey stay still, waiting, and April finds herself almost wanting to defend Karai further, to proclaim that she doesn't mean any harm, even though the kunoichi has fooled her before. Karai blinks at Leo, looking startled, and he adds hastily, "I mean, Shredder didn't... do anything to you... right?"
Karai blinks again and her shoulders tighten. "I'm fine," she says. "But none of us will be if he finds out you four are back in action."