Author's note: Thank you to the followers and to the ones who reviewed... this means some people actually read the strange products of my brain. I'm so happy.

I don't own anything, please review.

John was stunned. Did the tall one really just tell them that they had a „demon problem"?

He wouldn't have been surprised or concerned that they knew who Sherlock was – after his well-publicised suicide and his even more public return, it was to be expected – but these three... Why did they suddenly show up out of nowhere while they were discussing Mycroft? And what did they mean?

At least Sherlock didn't seem disconcerted. John had moved to stand next to him as soon as the leader – he supposed he was, since he'd been the first one to talk and was staring at them like he demanded answers – had spoken. His hand hovered over the pocket in which he kept his gun; he wouldn't hesitate to shoot in the moment one of the tried to attack them.

"What do you mean?" Sherlock asked calmly and John forced himself to relax. Ever since the consulting detective had returned, he'd been jumpier than before; he shouldn't just assume everyone was a threat.

Sherlock felt John relax. Good. They didn't know who these men were, nor why they were here; it would be better to ask them what they wanted first before shooting. Especially since two of them were armed. The one in the trench coat who hadn't spoken yet didn't carry a weapon; Sherlock was sure of that at least, even if he couldn't deduce anything else. But still, it was two guns against one, and he would prefer this not to turn into a fight. Especially since he still had Mycroft to worry about.

The younger one who had told them that they might have a "demon problem" (for once, Sherlock had no idea what he meant) bit his lip before answering, "I know this will be difficult to understand. But listen –"

"Look" the elder one interrupted him, "Your brother might be possessed by a demon, and we need to find out if it's true, and if it is, we need to waste the demon".

"Dean" the tallest said, visibly annoyed, "You are not helping. You should calm down".

"Calm down? I just spent eight hours in a flying death trap because some chick sent us on a demon hunt that might not even be a demon hunt and you decided we needed to earn money while hunting..."

"Dean, I do not believe you are making a good first impression" the one in the trench coat finally said, "and you slept during the flight. For two hours, at least".

"I just rested my eyes and – Cas, I thought you were sleeping. Don't you ever sleep?"

The other man shrugged. "I'm not used to it".

That seemed to make the elder brother uncomfortable, although Sherlock couldn't say why; he didn't say anything else, and the younger one continued where he had left off.

"There is no easy way to say this, but – we think your brother might be possessed by a demon."

"What?" John asked, obvious disbelief in his voice. Sherlock couldn't blame him. Mycroft hadn't been himself lately, but a demon? Really? Why would anyone come to such a conclusion? They had to be lying; there had to be another reason why they wanted to get into contact with him. But why would three strange men suddenly show up and tell him that his brother was possessed by a demon?

"I know it's not easy to understand" the younger man added, "but – "

"What is there to understand? It's impossible!" John interrupted him, taking out his gun.

"I suggest you tell us why you are really here".

Sherlock understood John's reasoning, but he was... intrigued. What did they want?

He decided to ask something else first, though.

"Who called you?" he demanded. He didn't have any reason to think they would be honest with him, but neither was there any cause to believe them dishonest. They hadn't drawn their weapons although John was pointing his at them.

The older one of them answered.

"Like I said, some chick called us, offered us money if we would take the case, said something along the lines of "We know about people like you". She called herself Anthea".

Sherlock had suspected as much; if anyone called them about Mycroft and it wasn't him or John or Greg –

It could only have been Anthea.

He would have appreciated a warning that they were coming, but Anthea had worked for the British Government too long not to keep a few secrets. And if she trusted these men...

She had been working for Mycroft for a long time now. She knew his brother. Sherlock had known her almost as long; his brother had put her in charge of his surveillance when he'd still been a drug addict and living off the grid. He trusted her, and she trusted him, although they had barely spoken in all the time they'd known about each other. She wouldn't send just anyone to meet him and John. And she wouldn't have used the name he and John normally referred to her by if she didn't think them trustworthy, or at least useful allies.

"John" he said quietly, and the doctor sighed and dropped the gun.

Sherlock looked at each of them in turn and finally asked, "Who are you?"

The oldest of them answered. Of course. Mycroft wouldn't have allowed Sherlock to answer a question like that, either.

"Sam and Dean Winchester" he said, indicating with his hand that he was Dean and his brother was Sam. "And this is Castiel".

Sherlock raised an eyebrow. "Castiel who?" He didn't appreciate people withholding information, especially if it was something as vital as a name. He could easily find out whether Dean and Sam Winchester existed; but he'd need more than the name of the Angel of Thursday to research the other man.

"Just Castiel" the man in the trench coat replied. "Or Cas, if you would prefer that".

Dean shot him a look that was difficult to interpret, but didn't say anything.

""Just Castiel"?" John repeated.

Castiel nodded. "I don't have a last name. I was an..."

"Alright, Cas, I think they've heard enough for the time being" Sam interrupted him. "Is there anywhere we can talk in private?" he asked Sherlock.

The consulting detective hesitated for a moment. If they wanted to talk about his brother, and they obviously did, there was no place where they could talk without being overheard. Mycroft had his eyes and ears everywhere.

His text alert rang out and he quickly took out his phone.

Your flat is clean. He thinks it is a malfunction of the equipment.

Apparently the corner wasn't as free from surveillance cameras as they'd thought, or at least Anthea had watched for the Winchesters and Castiel to appear and come to her own conclusions when neither them nor Sherlock and John had appeared on the next monitor. Either way, Sherlock had no reason to doubt her. He didn't recognize the number, it was true; but this only meant she was using a burn phone and didn't want anyone to know who had sent the text.

Especially not Mycroft.

And now that he'd reminded himself why he was at the street corner to begin with, and why the Winchesters and their friend without a past (he still wondered why he couldn't deduce anything about him) were here, the decision was surprisingly easy.

"Our flat is in the next street" he informed them, courtly, and felt more than saw John's surprised look. He knew the doctor was suspicious, and so was he. But Anthea had sent them, and she would never do that unless she knew them to be trustworthy.

John didn't say anything, simply followed him as he briskly made his way back to their flat.

Mrs. Hudson shuffled out of her door as soon as she heard them come in and looked at the strangers.

"Oh, hello Sherlock, I didn't know you were meeting clients..."

He decided to let his landlady believe that this was just any other case and simply smiled politely, but the Castiel said, "We're not clients".

Sherlock turned around. Dean sighed while Sam shot him an apologetic look and Mrs. Hudson asked, confused, "Sorry?"

"We are not clients. We are – "

Sam chose to interrupt him.

"We are – friends of – " he quickly looked from Sherlock to John and apparently decided that it was more believable that the doctor had friends Mrs. Hudson didn't know because he finished his sentence with "John's. We thought we'd drop by while we were in the country".

Mrs. Hudson smiled. "Oh, that's lovely! Why don't you go up. I just made tea, and the cake I baked should be cool enough to eat any minute now. I'll just bring everything up later".

Sherlock would have preferred if she didn't, but he knew Mrs. Hudson well enough not to protest. Dean didn't seem to be annoyed – on the contrary, he was delighted.

"That sounds absolutely wonderful, Miss – "

"Mrs. Hudson, my dear."

He winked. "Should have known someone as pretty as you would be married".

She chuckled. "Oh, John, your friends are quite as charming as you, I see". With that she closed the door and Sam looked at Dean, rolling his eyes.

"What?" his brother demanded. "She's nice".

"You just like the fact that you're going to get pie".

"So what? I just survived the flight; I deserve some".

"Why don't we go up?" John suggested, his voice brooking no argument, and Castiel was the first to walk up the stairs. He waited for Sherlock to come and open the door, though, and the consulting detective frowned. Something was strange about this man; not only couldn't he deduce him, but he was polite to a fault, and he obviously had no idea – judging by the look he'd shot Sam when the younger Winchester had interrupted him – why going around telling everyone the truth was a bad idea. And he, at least, was telling the truth, was believing that they were her because Mycroft was "possessed". Sherlock might not be able to make any deductions about his life, but he knew when someone was telling the truth. And Castiel was.

Predictably enough, Sherlock trusted him most, or rather, mistrusted him the least. Not only was it good to know that someone simply didn't lie; the consulting detective knew only too well how it felt like when everyone around was trying to hold up pointless social conventions when he knew them to be simply a waste of time.

He opened the door and let Castiel in, followed by Dean, Sam and John who had of course been the last to climb up the stairs to make sure no one tried to attack Sherlock from behind.

"So" he began, sitting down in his usual chair and putting the tips of his fingers together, "please, tell me why I should believe you".

John sat down in his chair while Dean and Sam took the sofa and Castiel remained standing.

"Well..." Sam answered, after having received a nod from his brother that told him he should explain everything, "Like Dean said, Anthea called us because she had heard about us. We're hunters".

"Hunters?" John asked.

Sam nodded. "Yes. We hunt demons, ghosts... anything supernatural, really".

"Of course you do" John replied but fell silent when he saw that Sherlock was listening,

"And" Sam continued "Anthea believes that your brother – Mycroft, is it? – is possessed by a demon".

"What makes you think that?" Sherlock inquired. He knew John didn't believe them, and in fact he was hardly convinced, but he had to check every option. Something was wrong with Mycroft.

Dean asked, his eyes boring into Sherlock's. "He's suddenly too cold? Uncaring? Not the brother you know?"

All of that was true, but he could not suppose it was enough to make Sherlock believe his brother was possessed.

"You ever notice his eyes turning black?"

He'd thought he had imagined it, a few weeks ago. Mycroft had turned around to leave, and for a moment Sherlock could have sworn that his eyes were black –

And, just like that, Sherlock had to admit that suddenly, their theory seemed a lot more plausible.

Author's note: I hope I'm doing the characters justice.

Please review.