A/N: This does take place in the world of Supernatural with all of the rules of that universe applying. I don't count it as a crossover as there are no character interactions between the two.

This is un-beta'd and un-Britpicked. That being said, all constructive criticism is most welcome. This is my first chaptered story so it's not too terribly long, only three chapters, but it's still a huge milestone for me. ^_^

It was just another day in the morgue of Saint Bartholomew's Hospital. Molly went through her routine, step by step. She was not bored, per se, but work had been slow as of late and a little excitement would have been appreciated. The sound of the doors opening caught her attention and she looked up, half expecting to see Sherlock or Greg entering. Instead, she was met with the sight of a young man making his way towards her.

"May I help you?"

"Detective Jack Williams," he introduced himself, offering his hand.

"Molly Holmes," she returned with a small smile, taking his hand to shake. "Are you new? I've not seen you around before."

"Just transferred in," he released her hand. "I'm here to see a body."

"Okay, may I see your badge, please." New or not, he was an unknown in her lab and that made her the slightest bit uncomfortable. Molly caught herself twisting her hands together and forced them down to her sides.

"Of course, of course." A badge was produced and flashed too quickly for Molly to get a good look before it was tucked away again. He gestured towards the drawers, obviously wanting Molly to lead the way, but she hesitated a moment more, assessing. Detective Williams was a bit rough around the edges, his hair too long to be professional and his suit in need of pressing. She had the passing urge to call and verify the mans identity, but brushed it aside as paranoia. Perhaps Sherlock's suspicious nature had been rubbing off on her.

She smiled and nodded at the man as she passed him and made her way to the wall of drawers. "Who did you need to see?"

"Sherlock," Molly called from the stairs leading up to 221B, bags hanging from both arms. "Could you give me a hand with these?"

Silence was her answer until she made her way into the kitchen. The find the man in question was elbows deep in his latest experiment and staring at her with wide eyes.

"Never mind," she said with an indulgent smirk, "I've got it."

The bags were dumped onto the counter to keep them separate from Sherlock's mess on the table. One of the first rules that Molly had laid down upon moving into Baker Street had been 'no mixing of food and biohazards'. It had been a battle at first, but Sherlock was mostly abiding by it these days.

"How was your day," he asked as she unloaded the shopping and put it away. "Any interesting bodies you need help with?" He was just itching for a case these days, but crime in London had been slow. A mixed blessing in the Holmes household, to be sure.

"Yes actually, I'm surprised Greg hasn't called you yet," Molly ruffled Sherlock's hair as she leaned over his shoulder, placing a kiss on his cheek and a jar on the table.

"What's this then?" He leaned down, trying to read the label without removing his gloved hands from their mess. "Ears!" His enthusiastic reaction never failed to bring a smile to Molly's face. He was the embodiment of a kid at Christmas. "This is why I love you, you know," he teased.

"I know," she laughed and made her way to the sitting room.

"So, what will Lestrade be calling me about?"

"I don't know if he will," Molly curled herself up on the end of the sofa, Toby joining her after she had settled down. "They've already sent some one down, a new Detective." She stifled a giggle at his raised eyebrow. It was no secret that Sherlock tended to be territorial. "I'm not sure how he'll fair though. He didn't seem interested in some of the more curious features of the report and kept asking the strangest questions."

Sherlock hmm-ed absently, already refocusing on his experiment. "Not likely to make it for very long by the sound of it."

"I would like you to take a look at the report at least, even if Greg doesn't call." Molly absently scratched behind Toby's ears earning her a descent purr. "If I hadn't triple checked my findings I'd think they were false. But it looks like the victims wounds are weeks old, with little to no signs of decay, which could be explained except for the many, many witnesses that had seen the man up and about all that time. It's almost as if, he was killed weeks ago, but didn't die until this morning."

She looked up to find Sherlock's intense stare directed at her. "Tell me about the Detective."

"Well," Molly thought for a moment, "He didn't seem curious what so ever about the injuries. He wanted to know about any odd markings." Her voice turned wry. "I told him three week old fatal injuries on a day old dead man was a bit odd." She gave a small laugh then tilted her head. "He also was quite stuck on the idea of smelling sulfur."

Sherlock narrowed his eyes, the rest of his body rigid. "What did you say?"

Molly tried to counter his solemnity with more humor. "I told him that between the morgue, the lab, and your experiments I'm quite use to smelling odd chemicals everywhere," her lips turned down when his expression remained fixed.

"Did he find what he was looking for?" Sherlock looked torn for a moment between withdrawing from his current scientific venture and potentially losing it, or staying where he was. "What did he say before he left?"

Molly was beginning to worry at the line of questioning, her eyebrows drawing down in confusion. "I- I don't know. He gave me his card, told me to call if I noticed anything out of the ordinary."

Sherlock, finally deciding, divested himself of his gloves and made his way to Molly. He sat himself on the table in front of her, his eyes intent. "Molly, I want you to stay away from this." At her continued confusion, he took her hands in his to convey the seriousness of his request. "The body, that man, all of it. Promise me you'll let some one else handle this."

Molly drew one hand away to lay on the side of his face. "You know I can't do that. I can't just push my work onto some one else." She brushed her thumb along his cheekbone. "What's this about, really?"

Sherlock broke eye contact first, looking down and away dislodging her hand from his face. After a moment of debate he looked back at her. "Your Detective Williams, describe him to me."

Molly watched him, trying to decide if this was a diversion or an answer. With Sherlock, the two often went hand in hand. She decided the best way to get an explanation was to play along. "Young, tall, pale coloring, slim. His hair was pulled back in a low ponytail and his clothes were low end at best." She stopped to think, knowing that he would want every detail. "He had a days worth of stubble. Oh, and I checked his badge, but I didn't really have time enough to do more than verify his picture."

Sherlock waited a beat, then two, to be sure that she was finished. "He was a fake." His voice rang through the silence. "Obviously," he added for good measure.

Molly blinked at him, trying to connect the dots as he saw them. Her first instincts had been correct after all.

"I want you to avoid that man at all costs." Sherlock reclaimed the hand that had fallen from his face. "I've seen his type before; reckless, obsesseive, not caring who gets in the way of his goal."

She could not help but see the irony of his description. Though Sherlock's nature had tamed down some what over the years, there was no arguing that all of those traits still belonged to the man that she had married.

"I don't want you getting hurt." The sincerity in his gaze caused a blush to form on Molly's cheeks.

"I promise," she replied without hesitation. "If he comes back I'll text you and Greg. I promise."

Sherlock said nothing. He pulled her from the couch and into his lap, his arms cocooning her smaller form and simply held her tightly in his embrace. She wrapped her arms around him, trying to comfort him the only way that she knew how.

The next day at work Molly was hyper aware of her surroundings. She jumped at every noise and caught her breath every time the doors were opened. She knew that she was being silly, Detective Williams had been nothing but polite while he had been there, but what kind of a person pretended to be law enforcement? Besides her husband.

Sherlock came to take a look at the body later that day, but could find no fault in her testing or her final results outside of their unusual nature. By the end of the week she had convinced herself that the whole ordeal was behind her and done with until, halfway through her shift, another odd case came through.

The two victims shared no similarities except for the level of strangeness to their cases. Molly had her phone in hand to text Sherlock, certain that he would be interested in taking a look, when the self-proclaimed detective from days earlier let himself into the morgue. The nature of Molly's text changed rapidly, 'He's here.' She hit send and slipped the phone back into her pocket trusting in Sherlock to alert Greg and to get there as quickly as possible.

"Hello again, Doctor Holmes," he greeted her with a nod. "I hear you've got another one for me."

Molly forced a smile, trying her hardest not to appear suspicious. She had never been the best at acting and had only been able to fool those around her after Sherlock's fall because she had genuinely been mourning his absence. Her legs moved her stiffly towards the man, her hands fidgeted restlessly at her sides. "I guess so." She laughed nervously for a moment, unable to stop herself. Thinking that the best way to buy time would be to play along, she turned abruptly and lead him once more to the refrigerator wall.

"So," her face was beginning to ache from forcing her smile, "I can guess who it is you want to see."

"If you don't mind." He stood relaxed, hands clasped behind his back. She could only hope that he did not suspect anything.

The drawer slid out and she pulled the sheet back. Williams had just opened his mouth to ask a question when the doors flew open with a bang. Sherlock strode in, looking as calm as ever, though Molly could see that he was anything but. His hair was more wild than usual, his cheeks flushed, and she assumed he had run a good way here. Though how he would have had to have been close to make the journey so quickly.

"Molly, dearest," he called as he crossed the room, "Are you ready for lunch?"

They had made no such plans, but she knew enough to play along.

"Just about," she answered, glancing quickly to the man beside her. She watched as Sherlock's eyes flitted over him while he closed the distance, taking in every detail, memorizing, connecting pieces of a puzzle that she could not see. "This is Detective Williams." Molly took a few casual steps forward, closing the distance between herself and Sherlock. This had the added benefit of moving her away from Williams and lessened the knot of tension in her stomach just slightly.

Sherlock looked down at her. His face softened for an instant to the look she knew he reserved only for her. The next moment he was stepping past her, emotionless mask firmly back in place. She noticed that he angled himself to stand between herself and the impostor. She could only hope that Greg would be there soon.

He offered the man his hand. "Sherlock Holmes, Consulting Detective."

Williams took the offered hand, his eyes widening with recognition. "Obscero inquit Deus! It's an honor." Sherlock flinched visibly at the man's words and Molly watched as the situation went from strained to strange.

William's held onto Sherlock's hand, his grip tightening. "Problem?" he asked, quickly pulling a flask from his side and flinging the contents at Sherlock. Steam rose from his skin where the fluid had splashed him and Molly panicked, assuming a chemical burn. She rushed at the mad man, pushing him back with all of her might. Luckily, she had surprise on her side, and the man fell back, losing his grip on her husband.

"Who curses in Latin?" Sherlock spat.

Molly spun towards his voice to see to his injuries, but there were none. Sherlock's skin was as flawless as ever, but his eyes... his beautiful ocean colored eyes were pitch black from the iris to the sclera. She faltered in her steps, unable to comprehend what she was seeing.

The room went out of focus around the edges when those ebony orbs met her gaze. Sherlock's furious expression shifted to something unrecognizable. She could not look away, not certain what she was seeing. Her eyes closed for a fraction of a second as she blinked and he then was gone. In his place were the smell of sulfur and a dusting of yellow powder on the floor.

Molly stood in shock for a moment. She was brought out of her stupor by the feel of cool water splashing onto her skin. She turned her head to see Williams in an offensive stance, flask in one hand and a dagger with strange markings in the other. Seeing the weapon, Molly instinctively took a step back from the man.

He regarded her with cold eyes before lowering the weapon.

"You're not a demon." His voice held a note of surprise in it.

"I'm sorry. What?" That had been the last thing Molly had expected the man to say.

His posture relaxed and he put the knife away. "Holy water," he shook the flask still in his hand. "It burns demons. Easy way to check."

Molly shook her head. "I don't understand."

The man's expression turned sympathetic. "I'm sorry to be the one to tell you this, but you're husband is possessed by a demon." At her blank look he tried again. "You know; Heaven, Hell, angels, demons, that sort of thing." At her continued silence he shrugged. "Whether you believe it or not's not my problem. Two people are dead and that is."

Molly was finally able to find her voice. "My husband didn't kill anyone." In a while or without good reason, but she left that part unspoken.

Williams shrugged again. "Maybe not, but that thing inside him did and it needs to be stopped."

A chill ran down Molly's spine. "How?"

He busied himself with putting away the flask, not meeting her eyes. "If I can, I'll exorcise the demon. Send it back to Hell and your Sherlock should be right as rain."

Molly's hand balled into fists. "And if you can't?"

He met her eyes again, his face hardening. "This'll do the trick." He drew back his coat to flash the blade at his side. "This isn't just any old dagger. Not easy to come by either. But it'll do the job, if needs be. It'll kill the demon for good."

She could finish the thought for herself. "And Sherlock with it."

He nodded. "If it comes to that."

The sound of running feet could be heard in the corridor and Greg finally made his entrance. A half dozen officers swarmed through the doors, guns drawn, and ready to help. Through it all Molly did not utter a word and met all questions with a blank stare. Williams was taken into custody and some one wrapped her in an orange blanket. They thought that she was in shock, and Molly let them believe it. The faster that she could get away from all of this madness the better.