I don't remember when I walked to Stapleton's lab with Sherlock and John. I suppose I was in shock, though instead of a blanket, Sherlock had draped his coat over my shoulders as I sat on a stool near him. He was scowling through a microscope at white crystals when my mind finally clicked back into place and I'd realized where we were and what had happened.

"It's not the sugar." I croaked out, wincing at my hoarse voice and clearing my throat as Sherlock continued on; probably too focused to have heard me. "Sherlock."

When he still didn't respond, I sighed and grabbed the marker he'd been using before leading it up towards the cheek he had facing me. That got his attention.

"If you mark me with that, I will ensure that we have fish for dinner."

I wrinkled my nose, setting the marker down. "You weren't listening."

He sighed heavily, turning to me in annoyance. "What?"

"It's not the sugar." I repeated, ignoring his frustrated tone.

It wasn't towards me, after all, not really.

"What do you mean, it's not the sugar. It has to be the sugar." Sherlock argued.

"Sugar?" John questioned, having overheard.

"The sugar, yes. It's a simple process of elimination." Sherlock rattled off in explanation. "I saw the hound. Saw it as my imagination expected me to see it. A genetically engineered monster. But I knew I couldn't believe the evidence of my own eyes, so there were seven possible reasons for it, the most possible being narcotics. Henry Knight. He saw it too but you and Sam didn't, John. You didn't see it. Now, we have eaten and drunk exactly the same things since we got to Grimpen apart from one thing. You and Sam don't take sugar in your coffee."

"I see. So…"

"I took it from Henry's kitchen. His sugar." Sherlock snipped shortly. "But Sam says it's not the sugar."

"Maybe it's not a drug." John tried, but I shook my head.

"It's a drug, John."

Sherlock sat down and pressed his fingers to his head. "But how did it get into our systems? How?"

He turned to me, but I shook my head, standing up myself.

"Don't look at me. I can give you hints, but you're never happy when I give too much away. You'll figure it out, but I just…" I winced, tugging his coat tighter around me as I remembered what happened back in the lab earlier. "I-I need a smoke."

"Good, yes. Perfect." Sherlock turned to John and Stapleton. "Get out."

"What?"

"Get out. I need to go to my mind palace."

John rolled his eyes, standing and grabbing his jacket as Stapleton continued to question him.

"Your what?"

Sherlock wasn't listening though and John made for the door.

"He's not going to be doing much talking for a while. We may as well go, as Sam said."

She was still confused. "His what?"

"Oh, his mind palace." John explained as they walked. "It's a memory technique. A sort of mental map. You plot a map with a location—it doesn't have to be a real place—and then you deposit memories there that… theoretically, you can never forget anything. All you have to do is find your way back to it."

"So this imaginary location can be anything? A house or a street?"

I nodded. "Most people use someplace familiar to keep track of things. Mine's a library, though I don't use it as often as Sherlock."

"But he said 'palace'." She gaped. "He said it was a palace."

"Yeah, well… he would, wouldn't he?"

John kept an eye on me while I smoked, rubbing at my temples and trying to forget what had happened. I knew it would take a lot more than just locking it away in the back of my mind, but that was how I was going to have to deal with it for now. I didn't have much choice.

"You okay?" John asked, heading over and sitting beside me as I snuffed out a third cigarette.

I scoffed. "Course not, but I'm not stupid. Dwelling on it isn't going to help me get over it anytime soon. I'll bump into him again anyway. That's the fun part about knowing everything ahead of everyone else." I commented bitterly. "I know exactly when he's going to pop back up again, what's going to happen when he does, and I get to live with knowing how everyone's going to get hurt. And I get to go through those thoughts time and time again to see what I can and can't give away. To see where I can change things to help and where I have to stand back and watch. This little episode just shows that I need to work harder to get over him and what he did to me. I won't be able to face him or Sherlock otherwise."

John was silent for a moment as I looked at the pack of cigarettes in my hands and considered lighting a fourth.

"I'm sorry." He finally said, making me look at him in confusion. "I… I never really thought of what you had to go through knowing the future and everything. To me it just seemed like something helpful, but it's not, is it? It's hard."

I looked back down, nodding, before he hopped off his own stool and gestured to the door.

"Come on. We best go check up on him and make sure he's not getting into more trouble."

I smiled a little at that and hopped down as well to trail after him as we headed back to the lab, grabbing Stapleton along the way. He was finished and demanded to get access to the computers, leaving John to guard the door as I hovered nearby; coatless after returning Sherlock's.

"Project H.O.U.N.D. Must have read about it and stored it away. An experiment in a CIA facility in Liberty, Indiana." He rattled off as Stapleton tried to access it, but she was denied.

"That's as far as my access goes, I'm afraid."

"Well, there must be an override and password." John argued.

"I imagine so, but that'd be Major Barrymore's. Sam?"

I blinked, confused for a moment as I considered just telling him. "Do you, uh, want to just know it? Or look clever?"

Sherlock smirked and I rolled my eyes, willing to let him do his thing and figure it out himself.

"Check his office. And it's not Churchill."

Stapleton was curious though. "Hold on, why are you asking her?"

"Long story and not one you need to know." Sherlock replied shortly as he gazed around Barrymore's office. "Password, password, password. He sat here when he thought it up. Describe him to me." He ordered Stapleton.

"You've seen him."

"He means describe his character." I piped in, wanting to rush things along a little bit with Henry possibly going nuts out on the moor by now.

"Uh, he's a bloody martinet, a throw-back, the sort of man they'd have sent into Suez."

"Good, excellent. Old-fashioned, traditionalist; not the sort that would use his children's names as a password." Sherlock rambled, gesturing to a children's drawings on the board above the desk he was now sitting at. "He loves his job; proud of it and this is work-related, so what's at eye level? Books. Jane's Defence Weekly; bound copies. Hannibal, Wellington, Rommel, Churchill's 'History of the English-Speaking Peoples'; all four volumes, but Sam said it wasn't Churchill."

He continued to look around as I fidgeted anxiously.

"Mid 1980s at a guess. Father and son. Barrymore senior." He rattled on, spotting a photo and getting John's attention. "Medals. Distinguished Service Order."

"That date?" John added. "I'd say Falklands veteran."

"Right, so it's Thatcher." Sherlock nodded and Stapleton looked stunned.

"So, that's the password?"

"No. With a man like Major Barrymore, only first name terms would do."

"Password's seven characters max." I mused and he nodded, typing in 'Maggie'.

The override password was accepted and he quickly skimmed through the information on Project H.O.U.N.D. before everyone spotted where the letters themselves had come from: the project leaders' last names.

"Hound." Stapleton breathed out, whereas John was grimacing at the information and photos on the screen.

I simply chose to look away, having experienced first had how quickly the hallucinogenic could cripple someone with fear.

"Project HOUND: a new deliriant drug which rendered its users incredibly suggestible. They wanted to use it as an anti-personnel weapon to totally disorientate the enemy using fear and stimulus, but they shut it down and hid it away in 1986." Sherlock summed up.

"Because of what it did to the subjects they tested it on."

"And what they did to others. Prolonged exposure drove them insane. Made them almost uncontrollably aggressive."

"So, someone's been doing it again? Carrying on the experiments?" John asked and Sherlock nodded.

"Attempting to refine it, perhaps, for the last twenty years."

"Who?" Stapleton questioned.

"Not a lead scientist, they'd be too old." I mused out-loud and Sherlock readily agreed.

"Someone who was old enough to be there at the time of the experiments in 1986, but young enough to still be doing something today." He spotted Frankland then and understanding dawned on him. "Maybe somebody who says 'cell phone' because of time spent in America. You remember, John?"

John hummed, frowning.

"He gave us his number in case we needed him."

Stapleton figured it out as well. "Oh my God. Bob Frankland. But Bob doesn't even work on... I mean, he's a virologist. This was chemical warfare."

"It's where he started, though ... and he's never lost the certainty, the obsession that that drug really could work. Nice of him to give us his number. Let's arrange a little meeting."

"No time." I interrupted him. "We need to get to the moor."

"Pardon?" Sherlock frowned and I pointed at John, just before his phone went off and he pulled it out with wide eyes.

"How did you—?"

I was rather surprised myself. "Lucky timing? I mean, I knew the call was coming, but ringing when I pointed was just dumb luck."

"Who is it?" Sherlock asked as John answered the phone and I answered him; tugging John and him from the lab by their sleeves.

"Mortimer. Henry's lost it, tried to shoot her, and has bolted into the moor thinking he's a monster. John? Did he actually get a shot off?"

"U-Uh, no." He said, hanging up the phone. "She said he believed he did, but the gun was empty."

I let out a sigh of relief. "Thank God. I thought I'd forgotten about the bullet in the chamber."

They both turned to me in shock as we reached the jeep.

"You disarmed the gun?"

I nodded. "You didn't think I'd just hang out at Henry's overnight because I felt like it, did you? I actually got the man to sleep after encouraging him to go to a bedroom upstairs. The huge windows he has were asking for him to have nightmares." I scowled. "And some stupid squirrel was playing in his backyard. Nearly gave me a heart attack, not to mention what it would have done to him. Gave me a chance to grab the magazine of the gun, but I was half asleep when I thought of doing that, so I couldn't remember if I'd grabbed the bullet out of the chamber or not. He would have missed Mortimer either way, but I'd rather not take the chance."

"Excellent." Sherlock grinned, picking up his phone to call Lestrade as he messed up my hair fondly before climbing into the jeep. "Lestrade, get to the Hollow. Dewer's Hollow, now. And bring a gun."

The group rushed down into the Hollow just as Henry placed the pistol in his mouth; no one saying anything about the weapon not being armed, because the fact that the man was disturbed enough to resort to this was worrisome enough.

"Henry, no! No!" Sherlock shouted, causing Henry to stand and wave the gun their way in his panic.

"Get back. G-Get away from me!"

"Easy, Henry. Easy. Just relax." John tried to sooth as Sam panted at the exertion of getting into the Hollow and winced at the pain in her ankle; which Sherlock and John had somehow missed in their previous concern.

"I know what I am. I know what I tried to do!" Henry shouted.

"Just put the gun down. It's okay." John urged, but Henry shook his head.

"No, no. I know what I am!"

"Yes, I'm sure you do, Henry." Sherlock said, trying a different approach. "It's all be explained to you, hasn't it? Explained very carefully."

"What?"

Good. Distracted him. Sherlock mused, continuing on. "Someone needed to keep you quiet; needed to keep you as a child to reassert the dream that you'd both clung on to, because you had started to remember. Remember now, Henry. You've got to remember what happened here when you were a little boy."

Sherlock stepped closer, but Henry was struggling once more.

"I thought it had go my dad. The hound. I thought—Oh, oh Jesus. I don't—I don't know any more!"

He shoved the gun back into his mouth, but Sam called out now.

"Henry! Henry, stop!"

He hesitated, looking at her as she worried.

"Nothing happened, Henry. I-I understand that you're worried about Mortimer, but you didn't do anything. You just made her worried and a little scared, but for you! She called us to help you! And you need to think right now, because Sherlock's trying to explain what's going on. Someone has been drugging you, Henry. Drugging everyone who's been coming into the Hollow and you need to remember, because none of this is your fault."

"W-What?"

"Henry, remember." Sherlock said, drawing his attention back to him as John shifted towards the man as well. "'Liberty In.' Two words. Two words a frightened little boy saw here twenty years go. You'd started to piece things together, remember what really happened here that night. It wasn't an animal, was it, Henry? Not a monster. A man."

Understanding began to dawn on Henry as John went and took the useless pistol from him.

"You couldn't cope. You were just a child, so you rationalized it into something very different. But then you started to remember, so you had to be stopped. Driven out of your mind so that no-one would believe a word that you said."

"Sherlock!" Lestrade called out, joining them as John helped calm Henry and Sam moved to Sherlock's side.

"You alright?" Sherlock muttered under his breath, knowing that they were undoubtedly being drugged up at this very moment somehow.

"For now." Sam said softly back and Sherlock made a mental note to keep an eye on her, should she show signs of experiencing what had happened back in the lab.

"But we saw it. The hound, last night." Henry breathed out. "We… We, we, we did. We saw—"

"Yeah, but there was a dog, Henry, leaving footprints, scaring witnesses, but it was nothing more than an ordinary dog. We both saw it. Saw it as our drugged minds wanted us to see it. Fear and stimulus. That's how it works." Sherlock explained. "But there never was any monster."

A long howl rang out then and all eyes went up to the edge of the Hollow as Henry began to panic once more.

"No, no, no, no, no!"

Henry soon crumpled to his knees as Lestrade caught sight of the dog up on the ridge, stunning John.

"Greg, are you seeing this?" John asked, understanding the look Lestrade gave him and turning to Sherlock. "Right. He is not drugged, Sherlock, so what's that? What is it?!"

"Alright!" Sherlock said sharply back. "It's thill here. But it's just a dog. Henry! It's nothing more than an ordinary dog!"

"Fog." Sam said, catching Sherlock's attention. "Aerosol dispersal. That's what it said in the file. It's the fog. T-There was a leaking pipe in the lab too. That's how John and I got it."

The hound started coming down into the Hollow then, snarling and growling menacingly. Sherlock spotted movement out of the corner of his eye then, seeing a man in a gas mask. He rushed over, confronting the man and ripping off the mask to see Moriarty's grinning face.

"No. No, it's not you. Not here!" He shouted, turning the man to see Frankland covering his nose and mouth. "It's the fog, like Sam said! The drug is in the fog!"

Lestrade quickly threw his arm over his face, but Sam shook her head.

"It's too late. The moment we were down here, the fog drugged us." She said, before spotting the hound shifting and her eyes widened. "Lestrade, the hound!"

"For God's sake, kill it! Kill it!" Frankland bellowed and Lestrade tried, but missed.

"John!"

John fired off two shots and hit the beast as Sherlock grabbed Henry and forced the man to look at it and see it as it truly was; just a dog.

"It's just…" Henry turned to Frankland in fury. "You bastard. You bastard!" He tackled the man as Lestrade tried to pull him off. "Twenty years! Twenty years of my life making no sense! Why didn't you just kill me?!"

They finally got him off as Sherlock frowned.

"Because dead men get listened to. He needed to do more than kill you. He had to discredit every word you ever said about your father, and he had the means right at his feet." He explained. "A chemical minefield. Pressure pads in the ground dosing you up every time that you came back here. Murder weapon and scene of the crime all at once." Sherlock laughed happily. "Oh, this case, Henry. Thank you. It's been brilliant."

"Sherlock." Sam and John both chided him.

"What?"

"Timing?" John replied.

"Not good?"

John went to respond, but Henry brushed it off.

"No, no. It's… It's okay. It's fine because this means…" Henry stalked towards Frankland. "This means that my dad was right. He found something out, didn't he, and that's why you'd killed him. Because he was right. He found you right in the middle of an experiment."

The dog wailed then, shifting and John killed it for good as Frankland bolted with Sam on his heels.

"Frankland!" Sherlock shouted, rushing after them as well.

"Frankland! Frankland, stop!" Sam cried out. "Don't go into the minefield! Please!"

He didn't listen though, racing through the forest and scrambling over the barbed wire. Sam cursed, throwing herself over it as well and managing to grab the man's leg before he could get much farther. He tried kicking at her to get her hand off, but she grit her teeth and held fast; long enough for Sherlock and John to get over to her and reach past to grab the man. They were still on the incline before the actual minefield, but were cautious enough as they hauled him back over and Lestrade cuffed him. With no possible chance of escaping now, Frankland sat on the ground as John and Sherlock went about untangling Sam from some of the barbed wire that had hooked itself into her pants when she'd dove over it to grab Frankland. It was then that Sherlock spotted the bloody bandages around her ankle and frowned at her.

"What is this? You got hurt?"

Sam winced as John pulled the last bit of wire off her and they helped her onto her feet cautiously.

"I told you not to leave me at the top of the Hollow last night." She grumbled, shifting painfully. "I couldn't remember whether the hound showed up there or not and lucky me, he did."

"Why didn't you tell me?" Sherlock snapped and she frowned up at him.

"When? While you were panicking about your senses being wrong? When you and John were having a tiff?"

Sherlock grabbed her shoulders, trying to get some sense into her. "You can't keep things like that from us!"

"If I'd told you, you would have shut me up in the inn and Frankland would've been dead!" She shouted back, making him stop as she thrust a finger out at the minefield. "I kept my mouth shut because I knew he was going to make a bolt for it! He would have ran right out there, stepped on a mine and blew himself up and I didn't want any more people to die because I'd said nothing, alright!"

Things grew quiet between the group as Sam finally pulled a hand through her hair and turned away.

"Let's just go. I-I can't do this right now."

The group agreed and they returned to their cars; Lestrade taking Frankland away and the Baker Street trio sending Henry home before returning to the inn in tense silence.

A plate was placed in front of John and I and he heartily dug in as I prodded at my food in silence. My legs had scratches on them from the barbed wire, but nothing extensive, and my ankle was rather sore as well. John had patched me up earlier though, with a clean bill of health so long as I changed the bandages on my ankle every so often, but it was morning now and I still hadn't slept. I had tried, but the moment I closed my eyes, it was Moriarty's laughing face grabbing Sherlock and throwing themselves off a building. Even now, I sat with dark bags under my eyes, only half awake and waiting for the man to just pop out of a bush with a cheerful 'Surprise!'. A steaming mug of coffee was placed before me, tugging me from my daze as Sherlock decided to join us.

"So, they didn't have it put down then. The dog." He commented.

"Obviously." John hummed. "Suppose they just couldn't bring themselves to do it."

"I see."

John smiled a bit. "No, you don't."

"No, I don't." Sherlock agreed. "Sentiment?"

"Sentiment." John nodded, though I knew that Sherlock probably had a very good idea of things, despite his claims that he hadn't a clue. "Listen. What happened to us in the lab—"

"Do you want some sauce with that?" Sherlock tried to distract the man, but he continued on as though he hadn't interrupted.

"That was you, wasn't it? You said you made a mistake. You terrified Sam and I because you were convinced the drug was in the sugar." John scowled, before turning to me. "And you knew too."

I nodded slowly, eating some of the eggs on my plate. "That's why I saw Moriarty instead of the hound. The drug gives you visions of what you fear most at the time. I wasn't afraid of the hound. I was afraid of what the drug would show me. My worst fear."

I smiled bitterly, but the subject was dropped and brought back to the sugar.

"Wait, so you got it wrong." John mused, smiling at Sherlock.

"No."

"Mm, you were wrong." He pressed. "It wasn't in the sugar. You got it wrong."

Sherlock finally gave in. "A bit. It won't happen again."

John signed. "Any long-term effects?"

"None at all. You'll be fine once you've excreted it." His eyes shifted to me then. "Though Sam might require a sleeping draught… Apologies again."

I waved it off. "It's fine. I knew it was coming. I thought I was ready for it, seems not."

"We'll work on it." Sherlock smiled a bit and I managed to return one, before I reached over and hit him hard in the arm.

"That is for the lab."

Sherlock frowned, rubbing at his arm. "Yes. Point taken."

We shared a laugh, but I felt a chill go down my spine as a thought occurred to me. God, Moriarty…