I heard Mikey's screaming when I was in the bathroom, of all places. I bet that's a new image for most people, a mutant 22-year-old male turtle going to the bathroom in the sewer. We might as well have gone right outside our front door, for Chrissakes.

I finished as quickly as I could (why would anyone wash their hands, anyway?) and overturned a stack of records in my haste to get to the bedroom. Nothing about the room stood out to me at first glance, but my usually laid-back, party-lovin' younger brother was a scary shade of light green, and I dreaded to think what could have terrified him to this degree.

Rushing to put a hand on either of his shoulders, I attempted to soothe him so I could get some answers. "Mikey, Bro, it's Donnie! I'm here! You're okay, shhh, you're safe. What's going on?"

Mikey's eyes rolled wildly, and moisture began to gather at the corners of his eyes. I realized with a shock that I had never seen him cry before.

Leonardo skidded to a stop through the doorway just in time to see Mikey force himself to focus long enough to point a shaky finger at one of the cots. Both of our pairs of eyes instantly followed where it was pointing to.

My first reaction was a slight frown. There was a small, pet-sized turtle on one of our cots. It was too clean to be from the sewer. And there was no way that anyone from my family ever, ever, ever would have bought a turtle and kept it confined as a pet.

I couldn't breathe. I couldn't speak. I frantically searched around the cot, and soon found what I knew would be there: a red, looped bandana that sure wouldn't fit Raphael's forehead now.

I heard a loud, ungraceful thump behind me as Leonardo sank to the floor, and I leaned against the nearest wall for support. Always the most sensitive of my brothers, I squeezed my eyes tightly shut and let the tears fall silently down my cheeks.

"Enough." We heard a compassionate, yet stern, authoritarian voice, a voice that we couldn't help but obey even in the hour of our grief. "We will address this crisis as a family. Come to my room. Now." Splinter used his cane to hobble to the cot and pick up Raphael, holding him to his chest as he left the room.

My muscles felt weary, and I felt no inclination to test their strength. Compelling myself past my anguish, I pushed off the wall and instinctually found Michaelangelo. "Come on," I said, touching his arm and pulling it gently. We supported each other as we followed Splinter's order, knowing that Leo was strong enough to make it on his own.

"Kneel," Splinter said, standing at the center of the room, and we each gratefully obeyed, glad not to have to support our own weight anymore. In the back of my foggy head, I knew that Splinter was not doing this to be insensitive; he knew that we needed our usual structure and routine in order to stay afloat after trauma, and he acutely felt the ticking of the clock, if indeed there was any time left to bring back Raphael.

Splinter placed our brother on the low table in front of him, and the turtle slowly began to explore this new territory, stopping at the edges of the table to evaluate the danger. Leonardo reached forward and picked him up. Holding him briefly in front of him, he put the turtle back down.

"That's not the Raphael we know," Leo said dully. "Raphael never would have let me pick him up without fighting for all he's got. That turtle has none of our awareness in him."

A fresh round of tears pricked my eyes, and I swallowed them back.

"What are our theories?" Splinter asked. "What do we think is going on here?"

"Raphael probably exposed himself to something, the idiot," Leonardo said, finding anger a less painful expression of his grief. "He never did fully give up his Nightwatcher gig."

"And the chemical formula had a delayed release?" I asked. "What could he have been around last night that would have taken ten plus hours to take effect? He was here all this morning."

There was a moment of silence as we pondered the pros and cons of this brainstorm. "What if the Foot is back?" Mikey asked. "Are they involved again?"

I doubted it. The Foot had never shared the vengeful passion of their late Master; they never understood why he cared so much about destroying a few mutants from his past. After the Shredder died, the Foot had mostly scattered to other cities, staying in small numbers to avoid detection and never returning to their former prominence.

"What other ideas do we have?" Splinter asked, walking slowly in front of us.

We looked at each other and back to him. "Sensei, what is your theory?" Leo asked quietly.

Splinter stopped, looking at a point beyond our heads, and we could tell that an internal struggle was going on. Finally he said: "I believe we have defied Nature as long as she will permit us to."

The den seemed colder, darker as our hearts wrestled with these words. "You believe the power of the ooze is wearing off," I said, in the deadpan despair that so often follows the shock of grief.

"I believe that we are, in a sense, addicted to the ooze. And this dosage has worn off." He looked at each of us in turn, his expression resigned but troubled.

"But—but we'll fight this, won't we, Master Splinter?" Mikey spluttered, wide-eyed.

"Yes, of course we will—I trained you all to be fighters, and that will not change now at this final battle. Do not feel the need to give goodbye speeches to one another. The way we have lived our lives is the testament to our love and devotion for each other."

I shivered. We were barely out of our teenage years, the time when everyone feels invincible. I did not think that it would end this way.

"Donnie, do you have any notes or anything from when the Professor was here?" Mikey asked.

I knew this question would crop up sooner or later, and my heart sank, knowing what my answer would be. "Yes, but I have the notes of the chemical configuration for the antidote only. The professor's mission was to destroy all the remaining ooze, so he wouldn't have given me instructions on how to make more."

"Can you figure it out based on what you already have?" Mikey's voice was urgent, insistent, hopeful.

I shook my head slowly. "It doesn't exactly work that way, Mikey…it's not just an exact reverse of the formulas."

"And the Professor did warn us that he would be hard to find, after such a dangerous episode as we had when he was here," Splinter reminded us. "And we are ninjas, not detectives. We will have to do some thinking about what exactly is our missing link. Leonardo, Michelangelo, I am releasing you now to search the city. See if you can find anything unusual that's going on, but I will be surprised if you do. Stay together at all times." We all knew the unspoken reason why they could not split up.

Mickey and Leo left, but I had not been dismissed. I looked at him intently, waiting for my orders.

"Donatello…" Splinter briefly put a comforting claw on my shoulder. "I know that you frequently carry a disproportionate amount of the burden on your shoulders. Do not trouble yourself if your scientific brain cannot compute an answer to this riddle of existence. Perhaps our time is up, and we are meant to return to the more basic way of life that we were created for."

My shoulders relaxed slightly. I cherished his words, but Splinter only had the power to absolve a certain amount of guilt. "Thank you, Master," I said sincerely. "Would you like me to review the Professor's notes?"

"Yes, in a minute. After you say whatever it is that you've been thinking of saying since our meeting began."

I cringed. I was the most emotionally perceptive of my brothers, but Splinter could read me like a book. "I'm sorry, I know you would have addressed this eventually, but…what are you going to do with Raphael?"

A look of raw pain entered our sensei's eyes. He cleared his throat, and I wondered if he would have choked on these words otherwise. "I will…I will have to find or create a large cage for him."

A part of me died at the thought of my brother under such degradation, but I pressed on. "Then, Master…I suppose we should communicate where the last of us should release us into the wild?"

Splinter paused, and met my gaze meaningfully. "Yes, I will release you and your brothers where you will be the happiest and most fulfilled."

Taken aback, I responded, "Why do you think you will be the last among us, Father?"

Splinter gave a small, tight smile, a trace of wistfulness in his eyes. "I was very, very old when I stumbled into the ooze," he said. "Yet I'm still here, and my young sons' time must be up. The ooze must affect rats differently than turtles." Splinter motioned for me to stand up, and touched my arm affectionately. "I tell you this not so you can further chastise yourself," he said firmly, and I looked down. He had read my mind again. "I tell you so you will know that the burden is not on you. I will take the burden upon myself. If I cannot bring you back to mutant form in a reasonable amount of time, then I will end your confinement and release you in an area that nature intended. I love you all very much, my son."