My name is Oroku Saki. For more than two decades, I have trained myself, mind, body and soul, for one simple goal… revenge.

A man I once considered a brother has sought to wrong me at every turn, destroy everything I hold dear. But now, that time is at an end. Just as he stole my daughter from me, I have taken his prized son. Molded him into the perfect weapon of revenge. And he is only the beginning. Soon, my wayward daughter will finally return to her rightful place at my side, and Splinter and his precious turtles… will die.

The mood inside the lair was quiet. Not a sole was in sight as the entrance hatch opened up. From there, a pair of eyes looked around, checking to see if they were alone. Finally, he leapt down, revealing himself to be Michelangelo, as he rolled onto the ground, his nunchucks in his hands. He looked around, seeing everything was where it should be and that no one had been there recently.

"Alright!" he called back to the entrance. "Coast is clear!"

Everyone filtered in, mutants and humans, all armed just in case. Raph was slowly carried down by Donnie and Splinter before being moved towards the couch.

"How ya feelin, Raph?" Donnie checked.

"Been better," Raph replied as they set him down on the sofa. "Still, nothin would perk me up more then jabbing my sai through Shredder's eye socket."

"You are still healing from our previous battle," Splinter told him. "Do not overexert yourself."

"I'm gonna reinforce the locks and change all the codes," Donnie declared, already grabbing his tools. "Just in case… well, just in case."

"I'll start going through the data you guys pulled from the Technodrome," April informed, taking her seat at the computer. "See if it can tell us anything about what they did to Leo."

"I'll make another round topside," Karai volunteered. "Check the area again for any Foot activity."

"Stay in constant communication," Splinter insisted. "We cannot risk losing anyone else."

Karai nodded, sliding an earpiece on before heading for the exit.

Meanwhile at Oroku Saki's mansion, Leo was training against several Foot Mechs, being watched by the mutants under Shredder's employ. Bebop and Rocksteady were both enjoying themselves as they watched Leo, but both Tokka and Rahzar had their reservations.

"Man, can you believe we got one of the turtles workin for us?" Rocksteady commented.

"I know, right?" Bebop replied. "Hey, ya think he can get us sodas if we ask?"

"I bet he'd probably even bow and offer them to us all regal like."

The two snickered as Rahzar scoffed.

"It's not right..." he growled softly. "No one deserves to be trapped like that."

"Agreed, Rahzar," Tokka replied. "But it is not our place to question."

"I know… but it does not mean that I have to like it."

"Hey turtle boy!" Bebop cried out. "How about gettin us a couple of drinks?!"

Leo said nothing as he continued training.

"Hey!" Rocksteady tried. "We're talkin to you!"

Once again, Leo ignored them. Annoyed by this, Bebop and Rocksteady walked over to him.

"Hey," Rocksteady spoke, reaching to grab his shoulder. "You're supposed to do what we-"

Leo quickly grabbed the hand and kneed him in the gut before flipping him to the ground. He then planted his foot on Rocksteady's chest, blade aimed right below the rhino's chin.

"I serve Master Shredder," Leo told him. "Not you."

"Hey, you can't just-" Bebop began to object.

"Yes, he can."

All mutants turned to see Shredder entering the room. Leo immediately backed off of Rocksteady, sheathing his weapons and bowing.

"Master Shredder," Leo greeted.

"Rocksteady, Bebop," Shredder addressed. "You are not to disrupt Leonardo when he is training. I want my greatest weapon to be at his absolute best."

"Sorry boss," Rocksteady replied.

"Yeah, we didn't mean nothin'. Honest."

Shredder just scoffed.

"Clearly," Shredder remarked before turning to Leo. "You have performed well, Leonardo. Take a Foot Mech patrol and scout the city for the turtles. I sense they are preparing to make their next move soon."

"Yes Master," Leo responded, getting up and heading off.

Meanwhile out in the city, Karai continued making her rounds, not finding any sign of Leo or the Foot. She stopped on a rooftop for a moment, tapping on her earpiece.

"Calling in another all clear," she called. "I'm currently on Madison Avenue."

"10-4," Donnie called back. "Take a break for a bit, Karai. You sound like you need it."

"I'm fine," Karai insisted, turning away. "I'm just-"

She cut off when she saw something on the adjacent rooftop. It was a water tower, one that she recognized. Almost in a daze, she made the leap, approaching the tower, realizing it was the one Leo had been using for a hideout during the citywide gang war. She leapt down towards the roof, walking up to the tower.

"Karai?"

"Still here… just… I found Leo's tower."

"Oh… you need a minute?"

"Yeah… I'll-" she was already beginning to choke up. "I'll call back when… when..."

"Take your time."

Donnie hung up for her and Karai slipped into the tower, already feeling her emotions rising up. Seeing the makeshift interior, and Leo's clear attempts to make the place livable, she finally lost it. Sinking onto the rough hammock, Karai finally allowed herself to cry. She hugged herself, curling up and just sobbing, wishing that things were different.

Not far away, Leo led a Foot-Mech patrol across the roofs of the city. As they landed, Leo looked up and saw the water tower. There was something about it, something that drew him to it. He looked at the tower, and for a brief moment, he saw a flash of something. Almost immediately, he got a massive headache, and the image disappeared. He shook his head to clear his senses, looking up and seeing something inside the tower. Drawing his swords, he approached, hearing soft sobbing inside. He slowly climbed up towards the entrance, causing a small creaking on the wood. Hearing this, Karai stopped crying, her tanto in her hand.

"Who's there?!" she demanded. "Come out!"

Just then, Leo walked into the room, causing Karai to freeze up.

"Leo…" she whispered.

"Karai," he greeted. "Master Shredder is quite worried about you."

"Leo, Shredder isn't your Master… Please, you have to remember." She began gesturing to the tower. "Don't you recognize this place? Doesn't it mean something to you?"

Leo paused for a moment before speaking again.

"Your time with the turtles is at an end. Either come back willingly or be hunted down along with them."

"Leo-"

"I'll give you until dawn," Leo interrupted, turning to leave. "Make the right choice, Karai. Your father is waiting for you."

With that, Leo disappeared through the entrance, leaving Karai alone. Karai just stood there for a moment, before the tears finally returned to her eyes. Fighting the urge to break down again, she took off towards the lair, wanting nothing more than to bring Leo home.

Down in the lair, Donnie just finished programming in new passcodes, taking a breath as he did before wiping his brow.

"There," Donnie relayed. "That should do it. April, how's it going?"

"Not too great," April lamented. "I'm finding a lot of files on this thing, but nothing that might help us."

"We were only able to get some of the database before we had to get out of there. Might not have gotten what we needed."

"And last time you tried sending a probe into that damn disco ball, it took almost three weeks."

As April continued scrolling, she saw something that caught her eye.

"Hang on…" she let out.

"Whatcha got?" Donnie asked, walking over to her.

"Something called Project De-Volition… it might be what we're looking for."

"De-Volition?" Casey repeated. "What does that mean?"

"Volition is our ability to choose what we do," Donnie informed. "So the removal of that… could be comparable to mind control."

April tried opening the file, but all she got was the blue screen of death, and many error messages.

"Damnit, the file's so corrupted it crashed."

"Must have glitched out when I removed the shell cell from the Technodrome's computer," Donnie realized before slamming his fist against the wall. "Dammit!"

"We're not sunk yet," April reassured. "But now, we need to access the Foots' database to find that file."

"And with the Technodrome so heavily guarded, our best bet is to infiltrate Shredder's mansion."

"Somethin tells me that ain't gonna be easy," Casey guessed.

Just then, Karai came back into the lair, her face red and her eyes puffy.

"Karai?" Donnie let out.

"You ok?" Mikey asked, walking over to her.

"I ran into Leo…" she informed them.

"What?!" Everyone let out.

"What happened?" Raph asked.

"He found the water tower. He told me I had til dawn to surrender, or I'd be hunted down, alongside you guys."

"Wait…" Donnie spoke up. "Maybe we can use this."

"Whatcha thinking D?" Mikey asked.

"We need to get inside Shredder's mansion. If the Foot believes Karai is surrendering to them, it can give us enough time to sneak inside and get what we need."

"Assuming you're up for this, Karai," April chimed in. "We know you've been through a lot, and-"

"I'll do it," Karai cut off. "If it means getting Leo, our Leo back, I'll do it."

"Great," Raph responded, trying to get up. "Now let's-"

"You will stay here," Splinter shot down. "You are in no condition to fight, and I will not lose any more of my children."

"Oh come on!"

"Sorry Raph," Casey told him.

"You'd better stay here too, Casey," April told him. "You're still healing yourself."

"What? Come on, April..."

"No. You both will stay here on this couch or so help me, I will chain you both to it."

"You four go," Splinter instructed. "I will watch over Raphael and Casey."

Casey grumbled as he sat down next to Raph.

"Guess we just gotta deal," Raph lamented. "No matter how much it sucks."

Back at Shredder's mansion, Leo returned with his patrol, approaching Shredder and bowing before him.

"Master, we encountered Karai out on our patrol," Leo relayed.

"Did you now?" Shredder responded, genuinely intrigued.

"I have given her until dawn to surrender. I hope that is satisfactory."

"It will suffice. Though I have my doubts that she will-"

"Master," Nakumo cut off, entering the room. "Karai… she is at the front gate."

Shredder perked up at this.

"Shredder!" Karai shouted, looking up at the security camera on the gate with a hateful expression, arms thrown wide. "I know you're watching this! Open the gate! You want me back, so here I am!"

...

"It has to be a trap," Nakumo pondered.

"Of course it's a trap," Shredder replied. "This is clearly a desperate ploy from the turtles to try and undermine my plans."

"How do you want us to proceed?"

"Bring her in, then triple patrols. If they truly wish to come to me, I will oblige them."

Outside, the gates opened up, allowing numerous Foot-Mech's to rush out and surround Karai. They quickly disarmed her and escorted her inside. She didn't fight, merely following them silently, her face an impassive mask. They dragged her inside, unaware that they were being watched from an adjacent rooftop by Donnie, Mikey, and April. Donnie watched through a pair of binoculars as the Foot-Mech's brought her inside.

"She's in," Donnie relayed.

"This almost feels too easy," April admitted.

"Getting in was supposed to be easy. The hard part is waiting for Karai to shut down the external security so we can get in."

"Man, I hate waiting," Mikey commented. "Makes me antsy."

"Believe me, I know," Donnie replied, watching the mansion with stern intent.

Inside, Karai was led through the halls of the mansion, finally brought into Shredder's office where Shredder was waiting for her.

"Saki…" She swore.

"Karai," Shredder greeted softer than usual. "Welcome home."

Karai just glared at him.

"Let's make one thing perfectly clear. I am only here so I can try and get through to Leonardo. To try and snap him out of whatever spell you have him under. I will never be your soldier again… or your daughter."

Shredder just glared at her.

"Take her away," he ordered.

The Foot-Mech's dragged her off as Nakumo approached.

"Keep an eye on her at all times. Do what you wish with the turtles should they try anything, but leave Karaia unharmed."

"Understood," Nakumo replied, bowing before heading off.

Elsewhere in the mansion, Karai was being escorted towards one of the rooms. Once there, the Mechs deposited her inside before heading out, locking the door behind them. Karai glanced around the room, which she recognized as her old bedroom. She went to a nearby table and looked under it, seeing if any listening devices were planted. Once she was sure it was clear, she moved on to check the rest of the room for any sort of cameras and listening devices. After finding and destroying all of them, she pulled back her sleeve to reveal a bracelet with a small turtle charm on it. She pressed down on the charm, revealing it to be a disguised comm unit.

"Alright guys, the Foot's blind in here," Karai reported over comms.

"Good," Donnie replied. "Now we need you to disable external security so we can get inside."

"Right. Give me a minute."

After looking around, Karai spotted a nearby air vent. She went over to it and, putting her all into it, pried the grate off. She then climbed inside the vent, quickly crawling through so she could get to the security room before anyone got wise as to their plan.

Inside the security office, Slash was keeping an eye on the monitors when he noticed the monitors in Karai's room suddenly went static.

"What the…" he let out. "Send security teams to check on Karai! Now!"

Several Foot Mechs quickly took off towards the room, leaving Hun to keep an eye on things. From inside the vent, Karai narrowed her eyes in disdain.

"Now how am I gonna deal with you…" she whispered.

Thinking fast, she kicked the vent hard, dislodging it and grabbing it before it fell. Quietly, she leapt down to the ground, ducking behind a large server. Seeing that Slash was still occupied, she slowly stepped out from behind the server and walked towards him. Before she had a chance to make a move, Slash suddenly spun around and grabbed Karai, slamming her into a wall.

"Nice try, Karai," he mused. "Did you honestly think it would be that easy?"

"Actually, considering they left you on duty, I thought it would be a lot harder."

She suddenly kicked him several times in the face, causing him to let go of her. She then landed on a server before leaping over Slash and landing on the back of his shell. She then struck a nerve on the back of his neck, causing him to freeze up. After a few seconds, he dropped to the ground, passing out. Once Slash was down, Karai made her way to the controls, shutting down all external security for the others.

"Security's down outside," she reported. "You're good to go."

"Nice work," Donnie commended. "We'll be there soon."

"I'll see if I can keep 'em busy for you," Karai responded before signing off.

Donnie, Mikey, and Aprill all pulled out grappling hooks and aimed them at Shredder's mansion. One by one, they fired them, latching onto the roof of the mansion. They then zipped across, landing quietly on the roof.

"So far so good," Mikey noted.

"Yeah, so far," Donnie remarked. "Mikey, find Karai and help her keep Shredder's forces busy. April and I will find Shredder's main office and see if we can access the files on his computer."

Mikey nodded before heading off, leaving Donnie and April to move towards the edge of the roof and drop down, to a ledge, allowing Donnie to reach into his bag and pull out a makeshift glass cutter he created. He placed it just above the lock of the window before moving it around in a circle, allowing him to pop out the glass circle and reach inside to unlock the window.

Elsewhere, Karai made her way through the hallways of the mansion, hoping to cause enough chaos to keep Shredder's forces busy. As she rounded a corner, she saw several Foot Mechs approaching. Thinking fast, she ran forward and kicked one into the others, causing them to fall over. She quickly scooped up the Mechs blade and began cutting down the robotic ninjas in rapid succession. She then spun around, slicing off one mech's head before stabbing it in the chest, ensuring it would not be able to get back up again. As it fell to the ground, she breathed in and out heavily, lowering her blade in exhaustion.

"I am out of practice..." she lamented. "When this is over, I am resuming my training head on."

"Could've fooled me."

She instantly turned around, aiming at, as it turned out to be, Mikey. The oranged turtle ducked his head into his shell in a panic. Karai quickly withdrew her blade, hesitantly peeking into Mikey's shell, just as he popped his head out.

"Mikey, I know stealth is a ninja's main weapon, but do NOT sneak up on me like that!"

"Sorry. So, where does a ninja go to cause a distraction around here?"

"This way," Karai gestured as the two took off.

Meanwhile, Donnie and April quietly made their way through the halls of the mansion.

"I managed to download the blueprints to Shredder's mansion," Donnie informed. "His main office should be down this way."

"We just need to get there without getting caught," April replied, taking a deep breath to steady her nerves.

The two peeked around the corner, seeing a small hallway leading to the doors of the office. No one was guarding it, allowing them to move in. April cracked the door open, allowing her to look inside.

"All clear," she whispered, allowing the two to head inside.

They carefully moved towards the desk, approaching the terminals.

"Watch my back," April requested, sitting down and beginning her work.

"You got it," Donnie replied, spinning his staff in preparation.

Donnie kept a constant vigil around the room as April got to work sifting through the files. As she typed away at the computer, the two suddenly heard a loud creaking sound coming from outside. Donnie motioned April to stay put as he rushed to the door, about to reach for the nob. Before he could though, the door opened, revealing Tokka and Rahzar behind it. The two mutants looked in on the two ninjas, clearly not surprised by their presence.

"I told you they'd be here, Rahzar," Tokka spoke up. "The orange one is always the decoy."

"Stay back," Donnie warned. "Or things are gonna get ugly."

Shockingly, instead of move in for the attack, both Tokka and Rahzar held up their hands in placating gestures.

"We did not come to fight you, turtle," Rahzar spoke up. "We came to aid you."

Donnie raised an eyebrow at that.

"What?"

"What Shredder has done to your brother..." Tokka grimaced, an expression matched by his companion. "It is an affront to nature. A fate none deserve. Not even you."

Donnie lowered his bo staff, still not entirely sure what to think.

"We… need to find the files on what Shredder did to Leo."

"There's an elevator behind that statue," Rahzar directed, pointing to the aforementioned statue. "It will take you where you need to go. But hurry, the rest of our… companions will be along shortly."

Having a thought, April looked around the desk, seeing a button on the underside of the table. She pressed it, causing the statue to open up, revealing a secret elevator inside. April and Donnie looked at each other for a moment before nodding and running towards the elevator.

Elsewhere in the mansion, Mikey and Karai found themselves duking it out with even more Foot Mech's, fighting back to back as they did everything in their power to hold them off. Mikey quickly shot out his chain at one Foot Mech and used the bladed end to slice its head off. He then pulled it back as he spun the bladed end in the air, waiting for the next Foot Mech to try something. Karai meanwhile stabbed and slashed at every Foot Mech that came close, allowing them all to drop to the ground. As they fell, the two ninjas took a moment to breathe, both incredibly out of breath.

"Please, please, please, tell me that was the last of them..." Mikey pleaded.

"Doubtful," Karai lamented. "It's only gonna be a matter of time until-"

Just then, a cloud of smoke suddenly appeared in front of them. As the smoke cleared, Leo stepped out, along with the Foot Elites. Mikey gulped in response.

"Leo..."

"Leonardo," Karai let out softly, pain making her voice crack.

"Elites, finish them!" Leo ordered.

The four Elites charged forward, their weapons at the ready. Mikey sprang forward, spinning both nunchucks as he engaged the Elites. He kicked the spear one in the face, knocking him back as he patted away an attack from the axe elite. He then held up his weapons to block an attack from the double blade elite before kicking him in the stomach. He then backflipped out of the way as the trident elite took a swing at him.

As Mikey engaged them, Kara rushed towards Leo, locking blades with him. She pressed as hard as she could, but he proved to be stronger, forcing her back.

"Leo… Leo, I know you're in there. You have to fight this. Fight what Shredder's done to you."

"There's nothing to fight against!"

"Yes there is!" Karai pleaded. "This isn't you!

Leo just shoved her off before rushing forward to press the attack, swinging his sword at her repeatedly. She did her best to block and evade the attacks, but Leo's speed was proving to be more than a challenge for her.

Meanwhile, Donnie and April rode the elevator down towards the sublevels. They made their way out, Donnie marveling at the technical prowess on display.

"Somebody's been busy," Donnie observed.

"Oogle later," April cut off, "Leo's counting on us."

"Right," Donnie replied, shaking his head. "Computer terminal should be around here somewhere."

The two quickly took off, hoping to find what they were looking for.

Back upstairs, Mikey and Karai continued their respective fights. Mikey quickly ducked under the axe elites swing before slinging his chain at the spear elites weapon and pulling it out of his hands. He chucked it at the axe and double blade elites, hitting them both in the face. He didn't get the chance to enjoy his victory before ducking under the trident elites attack and backflipping, kicking him in the face. Karai meanwhile, resumed her duel with Leo, doing her best to try and get through to him.

"Come on, Leo, I know you're in there, and I know you can hear me. Come back to me! Please! I don't want to fight you!"

"Then don't. Come home, and be with your true father."

"My father is dead! You're the one who showed me the truth! Don't you remember?!"

"Your father is-"

"Hamato Yoshi! That is my father! You were willing to die at my hands to make me see that! Have you really forgotten that, Leo? Have you truly fallen so far?!"

The two locked blades again, but this time, Karai could have sworn she saw something in his eyes. A brief flicker of recognition, brief but telling. Leo quickly succumbed again as he kicked her back. He prepared to take another swing, but Mikey's chain shot out, wrapping around the blade.

"Come on, bro!" Mikey pleaded, pulling the sword out of his hands. "Quit the crazy act! You're stronger than this, so start acting like it!"

Leo turned towards him, drawing his other blade. As Leo rushed at him, Mikey quickly chucked a smoke bomb at his face. Leo sliced through it, causing it to go off. Mikey and Karai made their escape in the smoke, the former calling Donnie.

"Don, you there?"

"Here, Mikey. April and I just found the computer terminal. Should have the file in no time."

"Better hurry! It's getting hairy up here!"

"Just hold out a little longer," Donnie insisted as April kept digging through the files. "Any luck April?"

"I think I found something..."

"Just download it. We can sort through it once we're safely back at the lair."

"Right. Just give me a minute. Need to do it right this time."

"Right," Donnie replied sheepishly.

April inserted a flashdrive in the terminal, downloading the files she'd located. After a few seconds, the download was complete, allowing April to pull out the drive.

"Got it. Now let's get out of here!"

"Right," Donnie agreed, pulling out his shell cell as he and April took off. "Mikey, we got what we need. Let's get out of here!"

"Nothing would make me happier."

Up top, Mikey and Karai made their way towards the exit.

"Looks like we're home free!" Mikey declared.

Before they could reach the door though, some unseen force struck them both in the stomach, knocking them back.

"Or not…" Mikey lamented.

"Foot Tech Ninjas," Karai swore.

The two sprung to their feet as more blows rained down on them by unseen enemies.

"I! Hate! These! Guys!" Mikey let out with each blow and punch.

Karai just swung randomly around the room, hoping to hit something, but was having no luck. Mikey reached into his belt and tried to pull out some smoke bombs, but they were quickly yanked from his hand before he could use them.

"Hey!" he cried out before getting kicked aside. "Those are mine! Give 'em back!"

As the two proceeded to get kicked around, Donnie and April finally made it out of the sublevels and caught up with the two of them.

"Foot Tech Ninjas?" April assumed.

"Oh yeah," Donnie replied, pulling out some smoke bombs of his own. "This should do the trick."

He then chucked them at the ground, engulfing the room in smoke and revealing the Foot Tech Ninas' presence. Mikey saw this and leapt into the air, kicking one ninja in the face. Donnie rushed forward and swept another off his feet before bringing his staff down on him hard. April ran up and swung her tonfa, hitting one in the face so hard, it's eyepiece cracked. Karai finished off by slicing one on the chest piece, shorting out his cloaking circuit so she could see him.

"There you are," she sneered before kicking him hard in the face.

As the last Foot Tech Ninja fell, the four quickly took off, finally making their escape.

"Tell me you got it," Karai demanded.

"We got it," April reassured.

"We'll start sifting through it once we get back to the lair," Donnie promised. "We're gonna save Leo."

"Let's focus on saving ourselves first," Karai insisted. "Mikey, you get your smoke bombs back?"

"Eyup!" Mikey declared, gathering them up off the ground. "Let's make like a tree, and get out of here!"

The smoke engulfed the entire outside courtyard, concealing their escape.

Later, Shredder was being informed about the infiltration and escape.

"So, the turtles were here," Shredder realized.

"Yes," Nakumo confirmed. "And somehow they managed to gain access to the sublevels. We still don't know how they found them, and our security system is in complete disarray."

"Karai… she always was thorough."

"We have to assume they found what they were looking for."

"Indeed… get me Stockman. We're going to have to accelerate our plans."

"Yes Master," Nakumo replied before exiting.

"Relish your victory turtles. By this time tomorrow night… the entire city will be mine."

Leo meanwhile was meditating in the dojo, trying to focus his mind. This proved troubling though as strange images kept flashing into his mind. Images of people, places, and things he thought sure he never experienced, but still felt familiar to him. The faces were blurry and unfocused, but a strange kinship could be felt with these figures. He tried to focus on the faces, to determine who they were, but the action only brought him a massive, splitting headache. He finally snapped out of his meditative trance, breathing heavily as he clutched his head.

"What's… wrong with me?" he hissed.