Chapter 1

It was the late afternoon when the headache hit him. As Donatello sat at his computer, bathed in the pale blue light of his computer monitor, the headache pulsed behind his eyelids. What began as a dull, rhythmic thud quickly progressed into a hammer-like, full-blown migraine. It beat at him until he couldn't see straight. There was nothing but the THUMP THUMP THUMP that beat at the center of his skull, pulsing in his sinuses, his eyes, his ears. His code melted into incoherent dribble before his eyes, the binary blurring on the computer screen. The pain forced his eyes closed, a hiss escaping from his clenched jaw.

'Oh god, this is it. This is how I go.' He thought to himself, cradling his forehead with his fingertips. He pried his eyes open to look at his screen again, only to close them a second later as a wave of nausea swelled within him. Donatello spent another minute with his eyes squeezed shut and his hands holding his head steady before he chanced to open his eyes again. Fighting against the knife that continued to stab him rhythmically between the eyes, Donatello managed to look at the screen long enough to save his work and turn off the computer monitor. A quick glance at the clock confirmed that he had been at work for five hours. It wasn't his longest stint, but a headache was understandable after that much screen time. Then again, he had never experienced one like this before.

'There's some aspirin in the kitchen,' he thought to himself, pushing out his work chair and standing slowly to avoid aggravating his stomach. A steady diet of pain killers and coffee had never failed him before; surly that would make the headache pass.

When Donatello reached the kitchen, he was relieved to find only Leo sitting at the table, nursing a cup of tea. His brother stared deep into the amber liquid with a look of stony concentration and Donatello could almost read his thoughts from the wrinkles on his forehead alone. He was frustrated with Raph again; there had been an argument about curfew last night that ended in a set of split knuckles. Raph took a swing last night and Leo ducked just in time, sending Raph fist-first into a pillar. Needless to say, the two had been silent to each other ever since, the tension stretching between them. Don was glad that he didn't have to deal with unspoken tension on top of a headache and appreciated the lucky break.

As Donatello clattered around the kitchen, Leo slowly came out of his trance. His white-knuckled grip on his teacup loosened and he observed Donatello as he rummaged around the cupboards for aspirin. Donatello shook two tablets into his palm and Leo raised his brows in surprise as he popped them into his mouth, taking his water like a chaser.

Leo glanced at the label on the bottle and remarked, "Extra Strength? Must be serious."

Donatello smiled weakly, his brow creased in discomfort. He massaged a temple as he set the cup in the sink, saying, "I've got a splitting headache out of nowhere. I think my skull is going to crack open any minute now."

"Maybe a nap will do you some good?" Leo suggested, testing the waters. He knew how much Don hated naps; Don resented every moment he wasn't awake and doing something.

That's why he frowned when Donatello didn't bristle at the suggestion. He nodded in agreement and stood with a grunt of effort, and Leonardo was almost positive his face paled when he stood.

Don sighed in defeat, barely looking at Leo as he spoke. "I think you're right. Wake me up for patrol later, alright?"

"Sure," Leo said carefully. If Donatello had been looking at him, he would have noticed the shift in Leo's brow from creases of irritation to worry lines.

But Donatello had his head bowed, rubbing circles into his forehead as he loped off to his bedroom.

He settled in under the covers of his bed, unable to keep his eyes open any longer. As he drifted off, Donatello's last thought was whether or not he could finish those blueprints before patrol.

-T-

He awoke slowly, his vision blurred and his limbs heavy with slumber. As he crawled his way back to consciousness, Donatello registered with a sense of relief that his headache was gone. The aspirin had clearly done its work. As he rose slowly from the mattress, he threw a glance at the clock. 11:13 pm…

10:13?!

Donatello cursed through his teeth as he leapt from bed, making a beeline for the pile of gear near the end of his bed. He threw on his gear, tying on his mask as he ran out his bedroom door. He raced to the door of his father's room and skid to a halt outside the door, flinging the sliding door open. Donatello hung onto the doorframe, his heart pounding as he waited for his father to speak.

Despite Donatello's sudden entrance, Master Splinter remained completely calm, barely twitching when the door flew open. He was bent over a book, one paw absently stroking the whiskers on his chin. The flickering candles that illuminated the pages of his book cast heavy shadows over his pointed face, turning his eyes into dark pools set deeply in his face. Master Splinter didn't look up until he had finished his paragraph, and when he saw his dishevelled son hanging in the doorway, his maw turned up in a smile.

"Donatello. I take it you slept well?" His was warm and soothing like stream of water washing over him. Master Splinter could calm Donatello quickly than anyone, and at his father's words, his heart slowed to a cant in his chest.

"Yeah, I guess," Donatello still sounded like he was half asleep, his speech abnormally slow. He frowned at Master Splinter's gentle smile; he had expected to be reprimanded for oversleeping. "But where did everybody go?"

Master Splinter's whiskers twitched and his eyes fell to his book, his fingers idly slipping a bookmark into his page.

"Donatello, please come sit with me," Master Splinter asked as he gestured to the cushion opposite him, carefully postponing his response to Donatello's question.

Donatello obeyed, sitting cross-legged on the cushion that was now much too small for him, but he would never admit that to his father. Once he was settled, Master Splinter leaned back to observe his son. Donatello was still sleepy eyed, the crust of his slumber outlining the corners of his eyes. His only reaction was a mild twitch of Splinter's snout, his eyes flicking over Donatello once more to assess his fatigue before he spoke.

"Your brothers left for patrol two hours ago," Master Splinter was gentle in his delivery, not wanting to upset Donatello. Although Donatello had interests outside of his ninjutsu, he took patrol very seriously and would be loath to miss it.

"I'm so sorry, Sensei. I didn't mean to oversleep," Donatello said, his apology showing his guilt. He furrowed his brow in concentration, and Splinter could see him calculating as he asked, "Do you think I could catch up with them? It's Thursday, so they're doing the C route. If I use tunnel 17, go topside, and cut across Manchester, I should reach them at Cisco's in less than twenty minutes."

"That won't be necessary, my son," Master Splinter interrupted . When Donatello looked confused, Master Splinter explained, "When they were unable to wake you, Raphael suggested that they take Mr. Jones to fill your place tonight. They are not expecting you to join them. They understand that you needed to sleep."

Donatello looked hurt at the realization that Casey had filled his place, his fingers flexing in his lap. His desperation making his words run into each other, Donatello insisted, "But Sensei, I know I can make it, I've got the route in my head. I messed up by sleeping in, but I'm sure I can fix it–"

"Enough, Donatello." The command left no room for argument. Donatello fell silent, his face pinched in guilt.

"You work too hard," Master Splinter said, reaching a paw across the table and laying it on his hand. "There is no harm in missing patrol just this once. Often our bodies know what we need more than we ourselves do, and your body made it very clear that you needed some rest. Do not worry. Just enjoy the time you have to rejuvenate."

Donatello seemed unconvinced, but he nodded anyway. He stood and bowed to his father out of habit, saying a quiet "thank you" before he excused himself from his Master's room.

It was only a few minutes after Donatello's departure that the faint sounds of his tinkering in the lab started up again. Master Splinter sighed when he heard the thud of a dropped textbook, exasperated with his son's inability to take a break. Sometimes he was worse than Leonardo.

There was nothing out of the ordinary about what Donatello had said, but his energy was off. He lacked the usual spark in his eyes, and it had nothing to do with his impromptu nap.

Master Splinter pondered his interaction with Donatello for a long time, still and thoughtful even after the sounds in the lab died down and he heard his other three sons shuffle into the lair. In the newfound silence of the lair, Master Splinter readjusted his position on his cushion, resting his hands on his knees. He closed his eyes and began to slow his breathing, making his breath pattern perfectly even. When his muscles were heavy with relaxation and his breath barely broke the quiet around him, he felt the tingles on the edges of his body. It began at the ends of his nose, ears, and whiskers, spreading gradually enveloped his head. The same sensation filled the tips of his claws and his toes, stretching up toward the center of his body until his whole body buzzed with energy. A quiet hum began in his ears, its source the center of his skull, and slowly increased in volume as the tingling intensified.

As his mind transcended his body, Master Splinter focused his energy on Donatello, who was fast asleep on the opposite end of the corridor. He resolved to discover what was at the route of his son's troubles, and heal him.