He knew when John's mind had started slipping. He saw it before John did, in the way his eyes had started going vacant and distant, his sentences trailing off midway. He saw, and he knew it was more than the blood loss and the near-starvation diet. Simply put, John's mind was beginning to shrink from trauma too great for even his soldier's body and mind to cope with. Much longer, and the man would break; it was as simple as that.

Sherlock had racked his mind desperately for a plan, for anything that would get John out of this. He'd begged his captors, pleaded (he'd told Irene he never begged, but he would for John) to take him instead, hurt him instead. They'd ignored him, pretended not to even hear him, and that galled nearly as badly as his inability to find a way out. Alone, he retreated into his mind palace, now haunted with specters and shadows, trying to block out the fear and the knowledge of what was being done to John while he waited.

He'd lost track of how long it was this time when they brought John back to him, covered in blood and bruises, a dozen bones broken, sobbing and gibbering incoherently. For once, they dropped John close enough to be in Sherlock's reach despite the manacles on his ankles and wrists, and he gathered John into his arms, trying helplessly to comfort him, soothe him, or at least use his own body heat to help keep John from going into shock.

"He doesn't look so good, does he?" Sherlock snarled wordlessly at the Irish lilt, pulling John's body against his. The doctor cried out fitfully; whether at the sound of his tormentor's voice or at Sherlock jostling his injuries, the detective wasn't sure.

"So very brave at first, you know. They all are-but he was more than most. Using the naughtiest language at me. You really should train your pet better, Sherlock." Moriarty crouched down, and Sherlock would have traded the world for another inch of chain so he could throttle the bastard, the monster who'd dared to lay a hand on John.

Moriarty laughed again with a manic gleam in his eye. "I've got a present for you." He pulled out a capped vial as Sherlock glared at him in silence. "You ought to recognize this. It's the poison in those pills that sorry little cab driver was handing around. Boring little fellow, but he got your attention. Think I can do the same?"

"Stop boring me," Sherlock snapped. "Tell me what you want, or go away."

Moriarty leaned forward, mere inches from Sherlock's reach. "I want you to kill your pet."

Sherlock recoiled at the statement, shifting John against his chest, but Moriarty only laughed. "Oh, no, no, no-is that any way to treat someone who's on a mission of mercy? Your little doctor is in pain, don't you think? All alone, being tortured by the terrible criminal...awful fate for him. His mind's going, you know. He's already started talking to people who aren't there. Soon he won't even recognize you." Sherlock's stomach clenched at the thought, and more so at the fact that Moriarty was entirely correct.

"Now, you might think it won't be long until he dies anyway. But, I have some very good specialists on my team. And I assure you, I can keep him alive for years. Screaming in agony, and begging me to kill him. But you've got the chance to end it now. Put him out of his misery." He smiled, the expression rather like the rictus grin of a cobra. "Just like putting down a badly injured dog, right Johnny-boy?" This time, Sherlock was certain John's whimper was a response to the sound of Moriarty's voice.

Moriarty grinned insouciantly and put the vial down on the floor, and then pushed it towards the detective with a rod. Sherlock snatched it up, looking at the liquid in the dim light of the room. Impossible to be certain what it was without thorough testing, but he could at least try. He shifted John in his arms, twisted the vial's top open, and sniffed the liquid, examining it closely. It had a faint acrid whiff that stung at the back of his nose, and a slightly viscous look when he swirled it carefully, both of which would be correct for an oral suspension of the poison the cabbie had used. He stared at the vial, trying to find a way out. For a moment, his mind filed through possible scenarios, including drinking the poison himself. Surely Moriarty would have little use for John without him.

"I wouldn't try drinking it yourself, by the way," Moriarty chuckled, his voice making Sherlock's jaw clench in anger. "If you do, I'll keep him just for spite-and none of your friends will ever find where he's gone. And there isn't enough poison to kill you both. It'd only make you both rather violently sick if you try to split it."

Sherlock ignored him, but suspected he was telling the truth on both counts. He had little choice but to take him at his word anyway, under the circumstances. Moriarty stood up and turned away, walking jauntily towards the door. "You've got an hour to decide, Sherlock. Choose carefully!"

The door slammed behind the consulting criminal, and Sherlock re-stoppered the vial, setting it down cautiously. John was trembling in his arms, eyes distant and blank, his blood soaking Sherlock's already filthy clothes. He gingerly took his sleeve and tried to wipe the blood and grime from John's face, as gently as he could. "John. John, can you hear me?" He didn't know what to do, didn't see a solution to this problem. He'd been racking his mind since they captured, but his every attempt had only made things worse, and only led to John being beaten and tortured more severely.

John turned his head very slightly towards him, but Sherlock couldn't be sure how lucid he was. Still, he had to try. "John, he wants me to-to kill you. What do I do? Logically, you are in extreme pain, and it would be better to spare you that, but I also-" He faltered, knowing that Moriarty had to be watching. No, it didn't matter. He needed to say it. "You are my only friend, John. I am not sure I can kill you, even to spare you pain." He closed his eyes and shifted John again, pressing his own head against John's bloodied hair. This was a matter of conscience, of sentiment, of heart, and he'd never had any of those until John came along.

He felt tears welling in his eyes-tears he hadn't shed since he was a small boy. "John...tell me what to do. Please." He was lost without his blogger.

John shifted just a little against him, moaning in agony. Sherlock sat up and his eyes snapped open, looking down at the battered doctor. "Don't try to move, John. You're injured." And it was his fault, all his fault.

Slowly, John's eyes fluttered open. He looked in Sherlock's direction, though his eyes were distant. Even Sherlock couldn't be certain whether John was really seeing him or not. "Sherlock...'s okay. 'S fine." He coughed a few times, wet and heavy-sounding-the beginnings of pneumonia, Sherlock suspected, though he couldn't count on Moriarty's pet doctors allowing it to kill him...

No. It was the only logical thing to do. He had to get John out of this; it was his fault John was being tortured to begin with. And if death was the only way to get him away from Moriarty...well. Sherlock was a sociopath after all. He'd do what had to be done.

With a deep breath, and a final, defiant look at the cameras, he picked up the vial, turning it slowly between his fingers, and then opened it. Looking down at his doctor, his blogger, his best and only friend, he spoke softly. "John." He rested his hand gently against the side of John's forehead. "John. I need you to do something for me."

-SH-

Some distance away, Mycroft Holmes was surrounded by files and folders, desperately trying to sort through security footage, criminal reports, anything that might give him a clue where Sherlock and John had been taken. His phone chimed suddenly with a text alert, and he took it out, knowing with a shock of violent clarity that it would be something dreadful. The text alert contained an address and two sentences.

Come pick them up. Bring a body bag.