AN: The story picks up a month before Chapter One, which was kind of like a preview of what's to come.

Timeline: (Edit: Sherlock Season 2. After Scandal In Belgravia. I know, it didn't happen in 2008, don't bite my head off.)

Supernatural Season 3. Just after The Mystery Spot.

Disclaimer: I own nothing.

Chapter Two: A Genius Possessed (One month earlier)

Sam and Dean Winchester were parked beside a lake in Utah on a cold February day. They sat on the hood of a '67 Chevy Impala, sipping beer and just relaxing. They had just finished a case in a town nearby. There was a nest of vampires. Now they're headless vampires. It was all pretty standard procedure. Now, they stared over the frozen water, thinking. Dean was the one to break the silence.

"So, we hit a bar tonight, and try to find a case tomorrow?"

"Yeah, sure." Sam nodded. "But, don't you want to try and find Bela? I mean, she does have the Colt."

"Yeah, but we're no closer to finding her than we are to finding Atlantis." Sam smirked.

"Well that's a new attitude."

"Shut up." Dean got up off the hood and opened the car door. Sam followed suit. They got in and Dean started the car. They drove into the nearest town and pulled into a motel called Dusty Rose.

"Home, sweet home." Dean said, opening the door to Room 3B with the key they had been given at the front desk.

Sam flung a bag on one of the beds and pulled out his laptop. He set it down on the table and sat down on one of the beds. Dean, meanwhile, fell face first onto the closest bed to the door and laid there.

"You know what?" Dean said, his face buried in the blankets, "Screw the bar. I'm fine right here." Then, his stomach rumbled, and he rolled over onto his back. "On the other hand…"

Ten minutes later, the Winchesters were walking through town on their way to a diner. They walked past an alley, and Sam stopped, making Dean turn around.

"What?" he asked his brother, who was looking into the alley with a confused expression on his face. "What is it?"

"Look at this." Dean walked back too meet his brother, and looked into the darkened alley. At the back, hiding amongst the garbage, was a big blue wooden box with the words "Police Box" written across the top.

"Huh. Must be an antique or a prop or something."

"Yeah, I guess so." They continued walking and got to the diner. On their way, a man wearing a tweed jacket, a bowtie and a fez on his head ran past them, bumping into Dean's shoulder as he passed.

"Some people have the strangest taste in clothes." Dean commented.

After they ate, they walked back to the motel, passing the same alley again.

"Hey, Dean. The box is gone."

"It is?"

"Yeah. That's weird."

"Maybe, but it's not our kind of weird. Come on, Sammy. I need alcohol like, now."

The rest of the night was spent at The Q, the town's local bar. Then, they went back to the motel and slept for a few hours. When Dean woke up, Sam was coming through the door.

"Dean, wake up." He said. Dean sat up and wiped the sleep out of his eyes. "Bobby just called. We got something. Something big. We've got to drive up to his place and drop off the Impala."

Dean stretched and got up.

"Drop off the Impala? Why would we drop off the Impala?"

"Because we can't drive across an ocean." Dean stared at his brother.

"You're losing me, Sam."

"We have a case. In England." Dean made a face.

"Why the hell are we going to England?"

"There's a demon. He possessed some sort of genius or something, and now he's committing 'perfect crimes."

"If they're so perfect, how come we found out about them?" he asked, half jokingly.

"His roommate said something was off about him. And after a long line of phone calls and repeated conversations, Bobby heard about it."

"What's his name?"

"Sherlock Holmes."

That night, they arrived in England. In America, it was 6pm, but in England, it was already 11pm. Dean stood at the window of their hotel room, looking out at London. Sam walked through the door, carrying a slip of paper.

"Okay," he said, "I've got the address. It's 221B Baker Street. The roommate's name is John Watson. We'll go in the morning."

"Sounds good. But, dude, we're in London. We are not going to spend the rest of this night in a hotel room. Let's go out, have some fun. It may be the only time I'm here."

"No, Dean. You're not pulling that 'year to live' crap on me. You go out, whatever. But, we got to work in the morning." Dean wrinkled his nose.

"Since when are you allergic to fun?" He sighed. "Okay, fine, stay in. I'm going to 'research the accidents where the people are'."

"You mean go to a bar."

"No, absolutely not." He paused. "In England, it's a pub."

The next morning, Sam awoke to the sound of the door clicking shut. Dean entered the room and put his jacket over a chair. Sam yawned and stood up.

"Dude," Dean started, "you would not believe the night I had. It- Well, let's just say that cops in England, pretty much the same as back home."

"Something tells me you didn't voluntarily go to them for information on the case." Sam said sarcastically. Dean winked.

"So, are we going to go?"

"Give me a minute, Dean. I just woke up." Sam grabbed clothes from his bag and went into the bathroom.

"Oh, sorry. I forgot you need an hour to do your hair." He yelled through the closed door.

"I'll be out in a minute."

Fifteen minutes later, they got into the car Dean rented, and drove to 221 Baker Street. They rang the bell, and a small, middle-aged woman answered the door. She looked at them expectantly.

"Uh, hi. Does John Watson live here?" Dean asked.

"Oh, Americans. Lovely." The woman replied. Sam and Dean looked at each other. They couldn't tell if she was being sarcastic or not. "I'm Mrs. Hudson." She smiled politely. "John's upstairs." She stepped aside, and the brothers climbed the staircase leading to the second floor. They found the apartment with the letter B outside the door. They knocked on the door, and they waited. Suddenly, something occurred to Sam.

"Dean, who are we going to say we are?"

"The FBI." He said, pulling out a fake badge from his pocket. Sam looked at him.

"Dude, really? We're in England. The FBI is American."

"Oh. Yeah. Right." They waited a little longer, but no one came to the door. "Where is this guy?" Dean knocked again. This time, they heard a call from inside.

"Who's there?" he heard someone say from the other side of the door.

"Um, hi. My name's Dean, and my brother here is Sam. Can you open the door?" They could hear the sound of a lock turning, and a short man with blonde hair stood opened the door just a crack, enough to see his face.

"Are you John Watson?" Sam asked.

"And if I am?" Dean took a step forward.

"Is your roommate possessed by a demon?" he asked. Sam stared at him with wide eyes. John looked at him, confused.

"Who are you?"
"We want to help." Sam said, pushing his brother back. "But, we need to know, have you noticed anything strange about your roommate lately? Did his eyes maybe turn black for a second? Did he cringe around salt? Can you smell sulfur around the place?"

"What strange questions." John looked in the hallway. "You'd better come in." He opened the door, and both Winchesters were shocked by what they saw. "Would you consider this strange?"

Around the small sitting room, papers were thrown everywhere. Pictures were crooked and the glass frames were cracked. Furniture was knocked over and tea was spilled. Sam and Dean walked inside looked around.

"I've been away for the weekend." John said, closing the door behind them. "I came back yesterday, and when I did, I found the flat like this. But, before I left, I noticed Sherlock, my flatmate, acting odd. Well, odd for him. So, I told him I'd leave for the weekend, give him some time to cool off or calm down or something. Well, it looks like that worked out well." He finished sarcastically.

"Yeah, okay. Um, listen, John. We're kind of in a hurry, so I'm not going to sugarcoat this." Dean started. Where Sam was gentle and understanding, Dean was straightforward and direct. "Demons are real. They look like black smoke, and they possess people. Right now, that's all you need to know. Now, we think there's one in your boyfriend."

"No, no. We're not-"

"So, I need you to tell me where he would go, because people are dying, and Sherlock's behind it." John stared at the ground, thinking.

"There- There is one place, maybe. There's an old abandoned factory he likes to go to. He goes there to think out about a case, or usually when he needs to go to his mind palace."

"His what?"

"Don't ask."

"All right. Where's this factory?" Sam asked.

"I think it's on the other side of London." Dean raised his eyebrows.

"He goes that far just to think?" he asked incredulously.

"He goes farther for less." John replied.

"So, we go to the factory." Sam said, heading towards the door.

"I'm going with you." John stated as if it were not debatable.

"Fine, just watch yourself." Sam resigned. "I don't want to have to worry about someone else."

"Sammy, you don't have to worry about me."

"Dean, I always worry about you. Especially now." He gave Dean a meaningful look, while John stood by staring between them both.

They left the apartment, and John waved to Mrs. Hudson on the way out.

"I do hope Sherlock's okay. You'll find him, won't you?" she asked.

"We'll do our best." John replied.

Dean went to get in the car, when Sam stopped him.

"Dean." He said.

"What?"
"Other side." Dean sighed angrily, and walked around to the right side of the car.

"Damn British."

Twenty minutes later, the rental car pulled up outside Dorisson's Factory, which had been closed for years, and was now sitting in an abandoned lot. Dean got out of the car cautiously. They didn't have their arsenal in the trunk, but they were hoping they weren't going to need it. It was just a demon, and they figured John might get angry if they hurt Sherlock. Dean took a can of spray paint out of his pocket, and Sam had a small book. If this all went smoothly, they should be out in a short while.

But, of course, nothing ever goes smoothly for the Winchesters. They couldn't remember the last time something had gone off without a hitch. There was always something they weren't expecting, weren't planning on. Well, all they could do was hope for the best as Dean kicked in one of the side doors. As he did so, John took a step back, a little surprised.

"You do that often in America, yeah?"

"You should try it." Dean insisted. "It feels awesome."

They entered, unarmed, into the dark, eerie building. The walls and floors looked dirty, the way they do when they've been left alone for years. There were cobwebs scattered, but the trio made their way through, constantly on the look out for any signs of movement. They heard a creak from above, but one hears so many moans from old buildings, and they shrugged it off as pipes. The hallway led to a door, through which was a large room, which was probably where most of the products were made before all the equipment was cleared out. Now, sunlight was filtered through dusty, dirty windows high towards the ceiling that was nearly fifty feet above them. Sam quickly drew a large devil's trap. He didn't know how he would lure Sherlock into it, but it was the only plan they had. When Sam had finished, he heard laughter from behind them and turned around to see a tall man in a dark purple shirt and black pants come strolling in they way they had come. He had dark, curly hair and defined cheekbones.

"This is Sherlock, I'm guessing." Dean remarked. The man smiled, and his eyes became fully black for a moment, then retreated back to their normal coloring. The demon spoke.

"No. Sherlock is just the meat suit I'm wearing. But, I quite like him. Very slim." He ran a hand down his abdomen and over his stomach. John, who was standing behind Sam, stepped forward.

"You get out of him!" he shouted. "Leave Sherlock alone!" The demon only laughed.

"And why would I do that? This man's mind. Half of it I don't even understand. But, the other half? It knows exactly how to commit murder without getting caught. This human could be a great leader or criminal, but instead he chooses to help people?" He said the words as if they had a sour taste. "It's disgusting."

"You get out of him right now," John said, his voice dangerously low. "or I swear I'll kill you. I'll kill you stone dead." Again, the demon laughed.

"Why don't you ask your friends here how easy that is. Barely anything can kill a demon, and you two boys don't even have the gun that can. Oh, John. Do you want to talk to Sherlock for a second? I wouldn't mind. Hold on." He said, jokingly. Apparently, he found this all to be very amusing. Sherlock shook for a moment, then he was breathing heavily. He looked around, a completely new expression on his face. It was no longer amused, but frightened and weary.

"John?" he said quietly. "I'm sorry. I'm so sorry." He fell to his knees, weak. John ran forward and knelt beside him.

"It's all right, Sherlock." John said, consoling him. "These boys are here to help you."

"But, you have to kill me. It won't kill the demon, but he can't do as much harm without my body." Suddenly, Sherlock shook again, and he laughed a sinister laugh. Sam ran forward and grabbed John's arm, pulling him back.

"Oh, what a hero." The demon said sarcastically. "Willing to die to save these people he pretends to think so little of." Suddenly, the grin vanished from his face, and his eyes grew wide.

"What are you doing?" he asked, not looking at anyone standing in the room, but at the wall behind them.

"No. No! NO!" he shouted. "You can't! How-" Sherlock shook again, and the heavy breathing was back.

"Sherlock?" John said, uncertain.

"It's me."

"How- how did you get control back?" Dean asked incredulously.

"Well, when he did it once, all I had to do was repeat the action. It's quite simple- Agh!" He fell to his knees in pain. "He's- he's trying to get control again. I- I can't…"

Sam and Dean stepped forward. They each took one of his arms. With his legs dragging behind him, they carried him into the devil's trap. Just as they stepped out, they told Sherlock,

"It's okay. Let him take control. We'll get him out of you."

"Wait!" Sherlock struggled to say. "He doesn't want you to know, but- Agh! But- But- He's not alone. There are other-" He let out a scream. "other creatures, here, in the warehouse. Not demons, but-"

The demon regained control, and stood up, his face contorted into a dark scowl.

"Do you really think he was telling the truth? Why would I work with anyone else?" But, the demon didn't get a chance to say anymore, because Sam started to read out of the book. The demon screamed and out of Sherlock's mouth came black smoke that disappeared into the ground. As the last of it passed his lips, he fell to the ground, unconscious. John ran forward and scanned his body for injury.

"He'll be all right." Dean said, looking at Sherlock over John's shoulder. "The demon rode him pretty hard, but he doesn't look hurt."

"Come on." Sam said, stepping up to the motionless body. "We'll help you carry him." Sam grabbed Sherlock under the arms, and Dean grabbed his ankles. John followed behind, feeling a bit useless, but he did what he could by opening doors and such.

Finally, they got him in the car, and Sam told John to drive him back to the flat and stay there.

"We're going to find out what other creatures he was talking about." Sam finished. Shutting the car door, he watched as John drove down the road. The brothers began to walk back to the factory.

"Now," Dean said, "we just hope he doesn't come back here like one of those heroic types. God, I hate those types. They always put themselves in danger."

"I don't think we have to worry about that. He has Sherlock to look after now. Did you notice anything… going on between them?" Dean looked at him for a second before responding.

"Thank God. I thought it was just me. Yeah, something's happening there."

By the time they finished the conversation, they were back in the big room again. It was now empty, so they continued through the doors on the other side, always careful enough to expect something to be on the other side. They searched through most of the first floor by the time their search was over. When they opened a door not unlike the others in the hallway they were searching, Dean quickly closed it again. Sam looked at him in confusion.

"What?" he asked.

"Shhh!" his brother warned. Dean very slowly eased the door open, trying to make as little noise as possible. When it was entirely open, Sam saw what was inside. There were about twenty people, with their wrists bound to the ceiling, bleeding from puncture wounds in their neck. They looked barely alive. There were a lot of other people in the room, about twenty, but they were all sleeping comfortably on beds and hammocks. Dean closed the door again to consult with his brother.

"Vampires." He said.

"Yeah, I guess. But, I've never seen so many."

"Must be a nest." They were silent for a moment, each lost in thought.

"We should leave." Dean said. "We'll come back tomorrow when we're ready for them."

"Okay, but we should take the victims with us."

"No." Dean said sternly. "If we do, they'll know someone was here. We need the element of surprise. Trust me, they'll be better off in the long run."

"Yeah, and what about those who don't make it to tomorrow?"

"Sam, we're leaving." Dean started walking back the way they came, and Sam reluctantly followed behind.

When they got back to the flat, they found John cleaning up the rest of the mess the demon had made. Sherlock was in bed, asleep. He still hadn't woken up. Sam and Dean spent the rest of the day talking strategy and weaponry.

"We're really low on supplies. As in, we don't have anything." Sam was saying. He sat on the couch, while Dean stood, pacing the room.

"Sorry if I don't know how to sneak a machete through airport security!" he countered. "We can ask John about getting stuff. In the meantime, how are two of us going to take out twenty vampires?"

"I don't know, but we've got to try."

"And if we die in the process? What happens then? Can we really risk our asses on this? If we die, who's going to stop Lilith? Who's going to take care of things we take care of, Sam?"

"Dean, this is big. It means something. I know it does." Dean sighed, fixed an overturned chair and sat down.

"Fine. Then we better think of something." They sat in silence, each thinking to themselves.

"Ready?" Sam asked.

"Hell yeah." The Winchesters entered the factory the next day. Dean held a machete in his hand. Sam had a large bowie knife. It was all they could scrounge up. They found the room more quickly this time, because they went straight to it. However, to their surprise, it was empty. The victims were gone, and the room had been abandoned. All of the beds and hammocks were gone. Dean and Sam looked at each other, worried. The vampires knew they were coming. That means-

"Look out!" Sam called, as a woman (they assumed it was a vampire) jumped down from a ledge above, and landed behind Dean.

"Maybe," the vampire said, "if you want to plan a surprise attack, you shouldn't discuss it right outside the door where any one of us could've been listening." Dean swung his blade, but the vampire ducked and shoved Dean back into a wall.

"Most of us have cleared out." She continued. "With all the victims, by the way. Looks like you won't be saving anyone today." She lunged at Dean, who was pushed through the thin wall and into another room. Another vampire, a man, hopped down in front of Sam. Sam raised his knife, but suddenly, the vampire's face changed, and his eyebrow was different, and when he opened his mouth, there were only two fangs, not a row of pointy teeth. Sam was momentarily stunned, but he recomposed himself.

The same change happened to the vampire Dean was fighting, only Dean took a little longer to adjust.

"What the hell?" He asked, pausing for just long enough to let the vampire jump on top of him and tackle him to the ground. The vampire straddled him, pushing him into the ground. Dean tried to get her off, but during the attack, his knife had been knocked aside, and he was helpless. The vampire bent down to bite his neck, but a look of shock came across her face, and Dean saw a stake sticking through her heart.
"Sam, that's not going to stop her. Get-" he started to say, but before he could finish, the vampire turned to dust, and the dust fell on him. Now, he was really shocked.

"What the hell?" he asked, sitting up and wiping vampire off his face. When his eyes were clear, he looked in front of him to see a woman with blonde hair holding a wooden stake in her hand.

"Hi." She said. "I'm Buffy."

AN: I hope you had as much fun reading this as I did writing it. Check back soon for updates.

Review, favorite, enjoy.

-M.