"Karai," Leonardo's voice came out in a whisper.

"Christ," Raphael uttered quietly beside him.

Karai stood before them holding herself as steady as possible and in obvious pain, she had been struggling ever since the day Leonardo had run her through with his katana to protect his daughter. They knew she had lived, her body had been temporarily repaired by magic and that had long since faded, but to see her like this now, weakened and a shadow of the warrior she once was came as a shock.

The crushing weight of his actions coursed through Leonardo as he took in the sight of her, the consequences were always difficult to bear even if there had been no other choice, Karai had been relentless in her pursuit to possess the Shredder Tengu's powerful secrets and her obsession proved to be her undoing. He regretted deeply that she had forced his hand but he was still sure of that choice and he stood unflinching under her accusing glare.

"Karai, we don't have time for this," Leonardo said sheathing his katana in one seamless action, "It's madness down there and we'll all pay the price if it continues, or is that what you want?"

"Do not blame me Leonardo if your mutt of a child cannot perform her duties! Had I possessed the book I could have released the power necessary without releasing that decrepit demon, now you have cursed us all!" Karai barked in reply.

Leonardo moved just in time to stop Quayla from launching herself at her old nemesis. He couldn't blame her really; Quayla's feelings were understandably on a knife edge around the woman who had inflicted so much pain upon her family. Still, he couldn't allow her to reach Karai, he clamped his arms around her and held her tight. "Please Cute, don't," he murmured into her ear as she tried to writhe from his grasp. His wife took a shuddering breath and froze, nodding once to let him know she would take no further action, it would be no victory to defeat her like this. Karai smirked and jutted out her chin, the city lights sparkling in the darkness caught in the black gloss of her hair. His brothers stood poised and ready to move around them but awaited instruction, their faces set with grim determination.

"This wasn't us Karai, the book is contained and you were the last person to breach it. Are you seriously telling us you had nothing to do with this?" He glanced at the foot soldiers surrounding them. They were in complete control - unlike the growing hordes beneath them.

"Your soldiers seem unaffected," Donatello spoke up and stepped forward, having come to the same conclusions as his brother he lowered his bo-staff and propped his weight against it. "Our information so far suggests at least some of them should be succumbing to this insatiable rage."

The leader of the foot clan paused for a moment. "What information do you think you possess turtle?" The bitterness had drained from her tone and she now sounded genuinely curious.

Donatello cast a sidelong glance at his family as if to gain their consent in his continuing, Leonardo inclined his head slightly in acknowledgement. Donatello swung his bag from his shoulder and instantly began rifling through his supplies, the foot soldiers around them stepped closer as if expecting him to produce a weapon but Karai held up a gloved hand to stop them advancing any further. He carried on regardless and pulled out a skeletal disc drive with a trailing USB lead which he hastily plugged into his T-Phone. From a side pocket on the canvas he produced the copy of the disc they procured from the rescued store owner and shoved it into the drive with a loud click.

"Donnie's got mad Mary Poppins skills," Michelangelo whispered in awe. Leonardo had to agree, their brother had packed more than enough to see them through any crisis.

The T-Phone stuttered into life and a flickering picture filled the small screen, Donatello tapped the glass a couple of times until the images stabilised and turned it away from him so Karai could see. "Earlier we encountered a store owner in distress, some Purple Dragons were causing trouble but as you can see,-" He indicated to the top of the screen, "Initially they were going to pass by but something stopped them, I think it might be a pheromone release triggered by an emotional response which seems to draw in the, ahem, shadier characters the city has to offer and the Shredder Tengu is using them to take control."

Leonardo had to suppress a smile at his brother's enthusiasm, even in this dire a situation his love of technology shone through. He watched Karai's face with keen interest as the video played over again, he could be mistaken but she looked surprised at what she was seeing, of course he'd been wrong about her before.

"I cannot answer why the foot clan are not affected by this malaise but I am not responsible so do not presume to involve me in your plans," Karai informed them with her usual air of disdain.

Donatello interjected before Leonardo could open his mouth. "Karai, is your water supply on the city system?"

She sneered. "No, it is not, for obvious reasons. Our supply remains untainted by the filth through which you crawl."

"...and ours is filtered at source," Donatello mused, "Not that I think we'd be at risk either."

"You think it's in the water system then Don?" Leonardo asked his brother, who nodded in assent, "Well that would explain why the demon's grasp is spreading so quickly. Question is how do we stop it?" He turned to the head of the foot clan once more, "We actually came to ask if you still have the magic-tech Chaplain developed, it won't hurt the citizens but it could rid them of the darkness and at least give us a chance to find the Shredder Tengu."

Karai recoiled slightly at his words. "You... do not know where the demon is?"

"Enormous, dark and freaky is MIA," Michelangelo volunteered with a shrug, "The apocalypse started without him, go figure."

"You must all follow me," Karai stated and whirled around sharply, she disappeared into a large nearby elevator and held it's imposing door open while she waited for them to follow. Her hand shook slightly with the effort of keeping it from closing but her face betrayed no emotion.

A murmur of trepidation echoed among the brothers, Quayla pulled Leonardo aside and hissed, "You can't expect us to follow her."

He shook his head. "I expect you to follow me. We need some answers, we can't fight this blind. It's a risk we have to take." Leonardo didn't wait for her to agree and strode into the elevator, he took the weight of the doors from Karai and waited for a response, his family had followed him this far, he had to believe they would again. Karai backed into the corner of the lift and stood, hands folded, her expression betrayed nothing of her intentions.

Leonardo stared ahead pointedly and watched his family carefully as they reluctantly holstered their weapons while debating the sanity of their leader. They knew he was right although the lack of other options had them all feeling cornered before they even entered the confinement of the elevator car.

"You married her."

Karai's voice was quiet but clear from behind him. His grip on the doors tightened and he turned his head slightly so he could see her in his eye corner when he replied, "Yes." He was surprised she had noticed the sliver of gold around Quayla's finger, his own chained band lay in their bedside drawer as he couldn't seem to get used to it banging against his plastron during combat. "Is Chaplain...?" He wasn't sure how to ask what he wondered, the two had seemed so close but he was far from her side this evening.

She pursed her lips. "Chaplain is no longer my concern. His meddling in things he could not comprehend have reduced me to this."

Leonardo's brow rose in surprise at her candour, away from her league of foot soldiers she almost sounded like the old Karai. "Chaplain was curing you with magic? We were amazed how you recovered so fast but we always suspected mystical intervention."

"Move," Raphael's voice grunted beside him, he whipped his head around and saw with relief that his brothers and wife were waiting to enter the lift with them. He moved out of the way gratefully and let them file in. Quayla gave his shoulder a squeeze on her way past to let him know she was prepared to put her own feelings aside.

The doors closed with a soft ping and the elevator began to descend, Leonardo noticed Michelangelo's knees working slightly, they were all still pumping adrenaline and being crammed into a lift was less than ideal. The youngest turtle began to hum to fill the awkward silence which was met with disapproval from all of the occupants so they continued down staring ahead in preparation for what was coming.

The lift slowed and after a gentle bounce the doors opened to reveal a darkened laboratory different to the one they had raided for data previously, small dots of LED picked out minute details like a console here or a piece of equipment there showing it to be a small room. Karai pushed a button concealed on the wall outside the elevator and then placed her palm against a gelatinous panel that glowed blue for a split second then the place whirred into life.

She led the group towards a large glass screen buried in the wall of the room, which promptly switched on in her presence. A small sigh of appreciation passed Donatello's lips, he of course could match the skill of whoever had created it but the issue of how to fund such endeavours still evaded him. Karai waved a hand at the screen and immediately photos of a bloodied floor with superimposed text laid over them in grids popped into view.

"It's the glyphs," Quayla managed to choke out in horror.

"But we destroyed them," Donatello uttered uselessly, "I cleaned the drive myself."

Karai shook her head and swept an elegant hand at the screen, the images of the newly assembled pages began to flip rapidly past them. The sheer amount of information she had at her disposal was both impressive and terrifying. "You were to believe you had succeeded, I needed more time to study the text. If what you are telling me is correct then the demon is acting truly out of character. Never before has the Tengu unleashed his hordes and stayed hidden, his ego would not stand for it nor his thirst for power. I can attest to that."

"Karai, what does this all mean?" Leonardo demanded.

She pointed at a particular page of the glyphs and suddenly looked to Quayla expectantly. "Well? What do you see?"

Quayla folded her arms across her chest and glared back at her. "I can't read them."

Disbelief registered instantly among the group, they stared at the blonde in shock.

"Cute, that stuff was inside you, how could you not be able to read it?" Michelangelo blurted out, he couldn't stop himself, they were all thinking it.

"So she couldn't be tortured into translating it while she bled out, it's simple strategy on the part of the tribunal," Leonardo answered frankly, he knew of course that the contents of the text had been as much of mystery to Quayla as they were him. That hadn't stopped him spending hours researching ancient writings however, knowing the glyphs had blighted his wife's life was bad enough but now they were stored within their daughter the secrets were almost too much to bear.

"It wasn't a choice. I've never had a choice where that cursed text is concerned," Quayla added quietly beside him. She then met Karai's accusing gaze, her anger had ebbed away to the point where she was willing to hear the woman out. She sighed, "What did you find?"

Something akin to pity flittered across Karai's face for a second before the cold front dropped, but then perhaps Leonardo always wanted to see that in her, just an ounce of compassion for her prior misdeeds. She was once an honourable warrior and something told him that same warrior was now battling for honour again but she was only fighting herself. "I believe the demon has possessed a new soul. The writings speak of another coming and to do so the Tengu must bond with a new host," she tapped the screen, "Here, there is mention of the spirit evolving and changing by invoking the demon and inviting him in, unfortunately I do not possess enough of the scripture to perform the ritual, thanks to your meddling. I had once hoped to redeem myself and be his choice but in my current state I would be mere fodder. I could not control the demon now even if I wanted to, my body is weak," she spat.

"But Karai," Donatello spoke up when stunned silence fell around the room, "How are we supposed to trace the demon?"

She tossed him a small orb, the foot clan symbol glowed red within suspended in an inky black fluid. "The liquid is residue left over from the demon's last attack. I was wise enough to collect what I could. When you are in the vicinity of the demon the connection will activate and the orb's temperature will rise," Karai turned away and flipped through another series of the screens, "There is one further thing Leonardo."

"Yes?" His voice was strained.

The foot clan leader moved to slowly face him, "The scripture states that the bearer of the book is the only threat to the demon's true form."

"No," Leonardo exclaimed in disbelief, he looked at Quayla aghast, her hands were trembling uncontrollably. "She's just a child."

"Perhaps your attempt to deceive the ties of the scripture were not as clever as you hoped," Karai retorted, she was referring to the moment Quayla's heart was stopped by the tribunal to trigger the book's failsafe and allowing her to be rid of the glyphs, "Now your daughter will pay the price."

Leonardo's heart ached, he foolishly believed he already knew the extent to which they had unknowingly burdened their daughter but this was almost too much to bear. As skilled as Jade had become she was no match for a demon at her young years. "Jade doesn't owe anything and Quayla didn't either," he growled at Karai and she hardened her glare.

"Sins of the father Leonardo," she cautioned him.

"You'd know all about that," he bit back as his control wavered, "We're leaving," he barked at his brothers and made for the exit.

Karai made a few curt assurances that they would not be harmed when they resurfaced on the roof, but they prepared for an ambush anyway. The kunoich's word held firm and the foot moved aside to let them pass, it made a shiver run down Leonardo's shell to have their eyes upon him knowing they could not act upon their desire to toss the party off the building to pattern the sidewalk below, some of the soldier's grudges against them ran deep.

"That bowling ball doing anything Don?" Raphael hissed, his eyes narrowed as they appraised the swarms congregating beneath them.

Donatello whirled around desperately holding up the orb, "No, no, ah ha wait," he lowered it and walked a few paces towards the west, "Yes, it's definitely getting warmer."

Raphael let out a noise of disapproval and gripped his sai a little tighter, "This is the worst game of hide and seek I ever played."

"Let's go, we're losing time," Leonardo urged them forward, he reached behind him to drag Quayla along, she was all but frozen to the spot. He tugged her arm a bit harder, "Cute, I'm gonna need you to snap out of it, come on."

"It's all my fault," she whispered horsely, "I should never have left the Ancient One, none of this would have happened."

Leonardo's sigh came out as a frustrated growl, he waved his brothers on ahead, clamped his hands to her jaw and made her focus on him, If the foot wanted to stare he would let them. "You know you did nothing wrong," he emphasised each word carefully, "You're stronger than this, don't let Karai get inside your head." He watched her nod slowly, her eyes were ringed with black and she suddenly looked exhausted, as if the battle had already been fought. "Are you still in pain?"

"It's worse than before," Quayla replied, her voice sounded distant.

"I'm sorry," Leonardo wrapped his arms around her for a brief moment then faced her again, "But we can't stay here. Can you make it to the next roof?"

She nodded again, took a deep breath and one by one they zipped silently down the waiting guide ropes to the roof below. They hit the ground running and caught up with the others who were still heading west. They had to stop periodically to adjust their route as the orb cooled for which Leonardo was grateful, at least it meant Quayla could rest, she seemed to be struggling more the closer they got to their target. He frowned as they changed direction again; the inky towers of the modern water processing plant that had replaced where they called home loomed on the horizon.

Bishop screamed out in agony as his limbs twisted again at an unnatural angle, he was sure a lesser man would have died many times over by now, given the hours of torture he was forced to endure. The demon was attempting to make itself comfortable in his skin and gain control, when it tore for what felt like the hundredth time the agent had to wonder if this was the one occasion he couldn't cheat his mortal existence.

He laughed, it was a bitter, wheezing sound and the demon laughed with him because although he too was trapped he could taste the opportunity for freedom, if only the vessel would surrender its carcass. There was something strange about this supposed human, his body was at odds with itself, the mind was his but when he pushed the body more it fought but no matter, the demon was patient now he could listen to the screams and wait.