Edited for correctness since last upload. Thanks to all who caught the mistake!

It was Sherlock who turned on the lights. What the camera had shown him mere seconds before had been a morbidly fascinating reaction to his experiment. Fear and stimulus. John had gotten ample quantities of both, and had reacted like the perfect realization of the drug's creator's dream. Hallucinating out a whole scenario, played out over far longer than Sherlock had hoped was possible. This was a very dangerous substance. He looked forward to studying it in a more controlled environment.

Sherlock approached the cage, wondering seriously if the hallucination would break upon John's seeing him. It seemed likely, but the drug had already proven itself wildly powerful. If it didn't, he might need some assistance. Helping others deal with fear wasn't exactly his strong suit.

He pulled back the curtain as unthreateningly as he could manage. The scene that greeted him, however, was not in the least what he had expected. John didn't cower from him or even try to attack him. John didn't do anything. He only lay limply on the floor, arms above his head in a protective gesture, apparently unconscious. Sherlock rushed over. Overdose was unlikely and he dismissed the idea. What he'd slipped John was barely a quarter of what he had himself ingested, and even though he had built up a decent tolerance over the years, he hadn't had nearly the reaction John had just displayed. There was also no sign of injury. No blood, no apparent trauma. There was nothing to suggest that the good doctor was hurt in any way.

Gently, Sherlock pried John's arms away from his face. John flinched away weakly, eliciting only a half-conscious whimper.

John was in pain. Oh, wow. This was very interesting. The reaction had gone beyond merely fear or hallucination and into the realm of a physical response.

Still, that information was far from comforting. Physical manifestations of imagined trauma could be almost as damaging as the real thing. It was rare, but hypochondria could in fact kill.

…And he'd just put his friend through a fear-heightened simulation of a deadly creature's attack. Good thinking, Sherlock, maybe later you can take on the mafia single-handedly or perhaps go skydiving without a parachute. Either would make great endings to this day of epic miscalculations.

Sherlock scowled at himself.

"John?" He asked uncertainly. Watson didn't reply, his eyes were still screwed up tight and his breathing was ragged and labored. "John!" He said again, this time more forcefully. "You're hallucinating. Dr. Watson, you are not injured." He placed a hand on the doctor's shoulder, trying to reassure him that it was all a dream, that he was alright now, that he was safe. John flinched away again, weaker even than the last time.

"Sh-Sherlock?" he asked. Sherlock could barely hear it, it sounded like he was choking through something liquid in his throat. Sherlock looked, it wasn't blood.

"John, listen to me. You are going to be alright, okay? In fact you're alright right now, you've just been drugged, this whole construct is a hallu-"

"Sherlock, I'm so sorry…" John gasped again.

"No, John, don't do this, you're all right, you're ok! John, please!"

"Oh, oh neg…"

"John, stay awake! Whatever you're feeling right now, whatever you think happened, it isn't real. That was all a hallucination. You're fine now, understand me?" John slumped back, his body falling completely limp on the floor, completely deaf to Sherlock's control-panicked speech. His face was greyish and he was still fighting for breath. Sherlock noted painfully that his friend's fight was weakening. His own fault. His mistake. He had to correct this. "Help!" He shouted. Why wasn't anyone else here? People knew about his experiment, people had helped to set it up. So where were they when it had gone wrong?

A young soldier, probably a guard, jogged up to them. "Sir, I'm sorry, you can't be in here anymore, it's-" The man paused, seeing John. "What's happened to him?" Sherlock sent him a murderous glance.

"He's hallucinating. Get some medics down here at once, I don't know how much good they'll do but if we can keep him alive until the drug wears off he's got a chance." The soldier looked at Sherlock as though he couldn't understand what the detective had just said. Sherlock sifted back through the words. The soldier's reaction was understandable, if unacceptable. "What's your name?"

"Gamble, sir. Lieutenant Mitch Gamble" Sherlock paused threateningly.

"Get the medics down here, Lieutenant, or the moment Captain Watson regains consciousness, I am going to suggest your immediate discharge." Gamble's eyes widened for a moment in fear. Not the right fear for the situation, but Sherlock figured it would do. Gamble ran off.

"John, open your eyes!" Sherlock snapped, worry almost crossing his mind-barrier. Now was a time to be stern, but far from a time to panic. He had to think rationally now or it would be over. He would lose, having created the mistake leading to his friend's death.

No. Not if he could help it. Not if he could turn this around. Think.

John Watson was a strong but open-minded individual, even more so since meeting Sherlock. It was rare and pleasing to find someone with that combination, but the traits were only serving to make the hallucination stronger. Perhaps if he could find out what the hallucination was of…

"Sir, my name is Captain Pole, could you tell us what happened?" Sherlock looked up. Two soldiers, each wearing the red cross insignia of a medic stood above him, pulling a gurney behind them. Sherlock stood to face them, somewhat threatening scowl still refusing to slip.

The other got to work while Pole waited for Sherlock to explain.

"He's hallucinating. He was dosed with an unknown compound, which induced a state of extreme fear. The dose of the compound itself would have been harmless; however, there were unforeseen complications—"

"Captain, he's hypotensive, 83/60, his pulse is 150, and blood oxygen content is well below normal. He's in shock, sir. I suggest we get him back to the infirmary." Captain Pole rounded back on Sherlock.

"Come with us back to the infirmary, I still have questions." He ordered, then set about helping the other soldier.

In the infirmary (Sherlock was pleasantly surprised to find that they had one), the pace quickened. Sherlock stayed out of the way, waiting for Captain Pole to return.

The code was an entirely fascinating process, and Sherlock didn't bother to hide his interest, an inaction that earned him several worried looks from the medics. In Sherlock's mind's eye, he saw what John presumably was experiencing. Assuming that the phone conversation had been anything close to accurate, the imaginary hound had attacked, leaving John broken and bleeding in the cage. That left the current scene horribly bloody, something his imagination imprinted upon the infuriating and bloodless reality.

Blood. It hit Sherlock far too late and he cursed his mind for slowing in the wake of Watson's predicament. John had even told him. Oh neg. O negative, a blood type. John had believed himself to be bleeding badly. His current symptoms, the shock and low blood pressure in particular, seemed to confirm that theory. He just had to prove it.

Sherlock pushed through the crowd of medics, smoothly deflecting their attempts to push him back. He reached for the dog tags they had set aside of John on the bed, in preparation for the possible use of a defibrillator. He was right; the blood type John had said was his own.

"Mr. Holmes, I assure you your friend is in good hands, just please stand back." Captain Pole was back, ushering Sherlock out of the way with quite a bit more force than the previous medics. Sherlock raised his arms in mock surrender and allowed himself to be pushed back against the wall of the small infirmary. The room had clearly never seen this kind of action, and was not in anyway designed for all four medics to be working on one patient. "May I ask you to wait outside while my medics see to your friend?" It was phrased as a question, but Sherlock had heard similar questions often enough to know it was meant as an order. He allowed Captain Pole to lead him to the door where he was out of the way, but stopped fast when Pole tried to urge him through it. "I need to talk to you about the circumstances of Captain Watson's illness."

"Fine, we can talk right here, where I can make sure you and your medics aren't about to do anything stupid." Sherlock stated, bracing himself against the doorframe with an air of stunning nonchalance. Pole, surprisingly, didn't try to force the issue.

"I assure you, my men are highly trained. They are very good at what they do." Pole said irritably.

"Yes, of that I have no doubt." Sherlock said, in a way that implied quite a bit of doubt. Pole seemed to notice this, but waited for Sherlock's continuation. "He's in shock. Have you figured out what kind yet?"

"Distributive." Pole said. "Possibly caused by an acute adrenal deficiency or sepsis of some sort. We'll get him sorted out."

"Wrong. Hypovolemic." Pole raised an eyebrow at the detective's revelation.

"That's impossible. He hasn't lost any blood, nor is he dehydrated to the point of shock." Pole corrected.

"Humor me. Cover your bases. The last thing he said before losing consciousness was his blood type. Why would we need to know that if not to replace lost blood?" Sherlock challenged him.

"And what state of mind was he in before he lost consciousness? We're not going to treat him for something he doesn't have, Mr. Holmes."

"Then you'd better tell your nurse not to give him the third dose of Narcan. You wouldn't want to treat him for that overdose he's also not having." Sherlock smirked, the irony of the situation not lost on him. If only he could get them to see what was going on, but he didn't have time to explain the situation accurately, and Pole was being infuriatingly suspicious. Understandable, but again, unacceptable.

"That's different. We have reason to suspect an overdose, based on your own story, Mr. Holmes. If you are not going to help anymore, please leave the room." Pole demanded, shoving Sherlock out the door.

"Wait! Listen. Whole blood would still bring up his blood pressure, which by your medic's own word seems pretty dire. Even if it isn't hypovolemic shock, which it is, it's a win-win scenario." Pole ignored him, stepped out after him, and closed the door. Sherlock heard the lock click with a sense of sudden finality. It would take a keycard and a password to enter the room again. He wouldn't be allowed back in. Pole fumbled with a radio earpiece.

"This is Captain Pole, requesting a security team to the infirmary. It turns out Mr. Holmes is being a bit of a problem."

Request acknowledged, Captain, on our way.

"You don't know what you're doing, Captain! The only chance your patient has to live is if you listen to me and treat him as though he has been mauled. That man is my friend, and I will not let you kill him!" Before Sherlock could finish, Pole's security team rounded the corner. Four trained soldiers against one wirey detective. Sherlock knew he didn't really stand a chance against them. He wasn't much good in an outmatched fight and was barely able to make a run for it before they were on top of him. He struggled wildly, but their combined weight and training forced him down and into handcuffs. The only thing he could think was that some time in in the last ten minutes, instead of making up for his experiment, he had only made things worse. If he had ever been so before, now John was really in trouble.

TBC...

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