A/N: This was orignally meant to be a Halloween fic, but real life got in the way. I have made up pretty much everything, except for the cemetary. If you enjoyed this fic, please review!

THE GHOST OF LONDON

"Three people dead in two days."

"Boring," Sherlock said.

"I don't think so. Didn't Lestrade call about this?" John asked, looking at the Times.

"I guess so," Sherlock answered.

"The three were chained, throats sliced. Marks were drawn on their chests with blood, but not their own. An inverted pentagram. There was an inverted pentagram drawn on the ground, various herbs were found, along with some kind of altar."

Mrs. Hudson shivered, "I don't like it. It's all very scary, don't you think, Sherlock? And it's almost Halloween. We should have a Halloween dinner."

"Mary would love that," John said, "She wanted to stop by today, but Ailee has caught a cold."

"That's too bad," Mrs. Hudson answered, "Sherlock, please find yourself a case."

She left the room; John turned back to Sherlock. "Call Lestrade. It's been a week since your last case and the only thing you've done since then is sitting on this couch and meditating."

Sherlock stood up, went to his room and closed the door.

The body was terribly violated, even more than the papers had described. The heart was cut out, but instead, there was a brush with hairs on the place the heart should have been. An inverted pentagram was drawn on the stomach along with some other symbols she didn't know.

"My gosh," She whispered as she looked at the body up close. The eyes were cut out, the holes were filled with herbs. The symbols weren't drawn in blood, they were carved into the skin. The middle fingers of the victim were cut off, from both hands, and the throat was slit. In all the years Molly was performing autopsies she'd never seen a body so violated as this one.

"What do you have here, Molly?" Sherlock Holmes asked. She was prepared for his arrival.

"Male, mid-thirties, 6 ft.3. The cause of death is definitely the sliced throat. The cuts were made before he was killed, although the eyes are probably cut out afterwards."

"I may hope so," Sherlock answered.

"These are the most violated bodies I have ever seen," Molly whispered, "And I have seen Moriarty's victims. I thought it couldn't get any worse."

Sherlock hovered with his magnifying glass over the body. "Oh, believe me, Molly. It can get worse."

"As long as you catch the one responsible," She said, covering the body.

He nodded, silently leaving the morgue. Molly didn't want to admit it, but she was terrified. This wasn't a simple serial killer, a psychopath who just killed and raped his victims for the fun of the killings, this was a murderer who'd planned everything out carefully, who had a purpose for the killings, for the bodies and the body parts. A prepared killer. And those were the kind of killers Molly feared.

Sherlock left after he told the Head of Barts security to keep the labs open for him since he needed to return later that night for research. He headed to the Library of Rituals and Religion, hoping the library would provide the answers he needed. The library was underground, hidden from the public eye. Only insiders knew it. Sherlock happened to know the librarian. The library contained some very rare and dangerous religious documents that could harm many if leaked.

"Hi, Lara. I need a book that can help me find the meaning of some symbols. Do you have one?" He asked.

Lara smiled. "Good to see you again, Sherlock. Walk with me, please."

They made their way to the back of the library, to the oldest stacks. "This is the right one," Lara pulled out a thick, old book and blew the dust off it. "The encyclopedia of symbolism and symbols. It's the latest edition from 1856." She handed him a pair of white gloves, "Please don't kill the book, it's one of the few left."

Sherlock walked with her to the reading table and opened the door. "Thank you for your help, Lara."

She smiled and left. He got his phone out and opened his photos app. The encyclopedia contained every single symbol, from the Romans to the secret UK organizations in the early 1800s. Reversed pentagrams were symbols of power. Some Satanists used it, some not. Sherlock spent hours hovering over the book until he'd found the meaning of the other other symbols were an anti-possession symbol, a symbol to draw ghosts, and a symbol to take the breath of life away. That symbol was carved into the chests of the victims. The symbols painted on the walls were the darkest ones, pure black magic. They were resurrection symbols.

"Oh goodness," Sherlock whispered, "There will be another one."

He got up, gave the book back to Lara and hurried out of the library, climbing the five hundred stairs to get back on street level. The library was a ten-minute walk from 221b, so he ran to get there in 5. He had no idea what the ritual killer was about to do, but he knew there were people at risk.

Everyone was gathered at the apartment for a Halloween party. Mrs. Hudson had done an excellent job decorating 221b. She was standing in the hallway, dressed up as a witch. "You're late, Sherlock," She said, handing him a black cloak, "I got you a costume."

"What am I supposed to be?" He asked.

"A vampire," She said, "Everyone's upstairs, please hurry. You're very, very late."

"You don't understand, Mrs. Hudson. We need to leave, right now," Sherlock spoke hastily.

Mrs. Hudson shook her head and pushed Sherlock up the stairs, "Go tell that to John."

He put the cloak on and went to the flat. It was entirely crowded with people. John and Mary were dressed as Hawkeye and Black Widow, their 3-month-old daughter Ailee was dressed as Eleven. Greg and Molly were chatting, and Mycroft was pouting.

"Sherlock!" Mary said, "You're finally here."

"We need to leave, right now," Sherlock said, "I have information about the murders."

Lestrade stood up, "Don't mention it, Sherlock. We've got the killer. It was some drug addict who believed that he could raise the death."

"Technically, he performed the right ritual," Sherlock answered.

"What did you use, Sherlock?" Mycroft asked.

"Nothing, I'm clean."

"Sherlock, I believe you. I'll come with you," Molly said. She wore a Ghostbusters suit, completely with "Holtzmann" nametag.

"Thank you," He said. They went outside, back on the streets. Baker Street was crowded with adults and children, trick-or-treating. "What's wrong, Sherlock?"

"I have a lead on the killer," He said, "I need you to come with me." He got a gun out of his coat. "Protect yourself."

Molly hesitated but took it. "Fine."

Sherlock led her to West Norwood Cemetery. It was a cloudy night, and fog started appearing, but the full moon could be seen. "The killer will perform his next sacrifice on the oldest grave here since it's sacred ground."

"What do you mean, sacred?" Molly asked as they walked over the cemetery.

"This cemetery was established in 1837, but people have been buried here for centuries. This was a sacred place for the druids, especially for human sacrifices. London has these…lines, if we have to call it something. They cross. These crossings are sacred and of enormous power. You can call demons, spirits, witches, anything supernatural if you perform the right ritual."

Molly was hesitating, seriously wondering if he was as clean as he said he was. This didn't sound very clean. "How do you know all of this?"

"My friend Lara," He answered, "She's an expert. We've got a library stacked with books on this kind of subjects in London."

"Lara, right," Molly mumbled.

"The killings were part of a bigger ritual. The killer is sacrificing humans in order to raise the dead. He has to sacrifice four people in three days. The last killing has to be made on sacred ground. He will raise hellhounds, let evil loose onto the earth."

"Since when do you care about the earth?" Molly asked, "And why did we have to leave 221b?"

"221b is a crossing as well. Used to be a cemetery."

"So why are we here?"

"Fifty-fifty chance. John's informed of everything, he's keeping the house in lockdown. No one can get in or out."

They approached lights. "Get down," Sherlock whispered, "We have to hide behind the headstones."

Molly simply obeyed. They crawled closer and hid. There were torched placed in a circle, and a man fully clad in white was standing in the middle of it. Another blindfolded female was tied down on a stone altar. The man was reading Latin from a book."I call you here, peaceful spirit. Please, return to earth as I make this sacrifice," Sherlock translated for her.

The white-clad man cut his arm open and poured blood into the mouth of the victim. Molly looked at Sherlock, whispering "Why aren't you doing anything."

He put his fingers on his lips. Suddenly, Sherlock started moving, crawling to the altar. "He'll see you!" She whispered.

Sherlock stood up, slowly, pointing his gun at the man. "This is the end."

The man saw Sherlock but ignored him. "Spirit, I call you, please return to earth for this sacrifice."

Molly ran over to Sherlock, not really realizing what she was doing. The man saw an opportunity and pushed Sherlock down on the altar before stabbing his leg. Molly stepped back, keeping her hand in her pocket. The man moved over to the blindfolded woman. She was crying, begging, screaming. Molly couldn't watch it any longer and got her gun out. She was a steady shot, Mycroft had learned her how to shot.

"Ego video meam uxorem,"* the man whispered.

"Not today, you bastard," Molly said. She pulled the trigger and hit the man in his leg. He screamed and fell down. Molly paralyzed. Sherlock looked at her, surprised. Molly ran over to the woman to untie her, while Sherlock tended to his own wounds. "You're safe now," Molly spoke softly. The woman started crying hysterically and curled up in a ball. The man on the ground was bleeding heavily. "We need to call an ambulance!" Molly told Sherlock as she started applying pressure to the wound.

"Already on their way," he answered.

The ambulance and police were there within 5 minutes. The man was rushed to the hospital and Sherlock, Molly, and the unknown woman were taken to the Yard.

Lestrade sat behind his desk in his cowboy costume, nervously tapping his foot. "Bloody hell, Sherlock. How did you know about this guy?"

"I didn't," He answered, "It was just a matter of deduction and help from some acquaintances."

"This guy is insane. Human sacrifice and rituals… It's all fake."

"Don't be so sure of that," Sherlock answered, "If you would excuse me, I have some other matters to attend."

Molly was sitting outside Lestrade's office, playing with her Holtzmann-name tag. "We're free to go," Sherlock told her.

Molly smiled. "Sherlock?"

"Yes?"

"I had a nice time ghostbusting tonight."

Sherlock wasn't sure how to react. "Erm, that's nice to hear. Thank you for your help."

"Do you want to get coffee?" Molly asked.

"I do believe we deserve coffee after tonight," he answered.

*Translation Latin text: I see my wife.