A/N: Yup, the new chapter is here! (grins)

First of all, though, GOSH! There's so many of you who want to see this story continue. (BEAMS) Thank you, from the bottom of my heart, for your reviews, listings and reading! I had my doubts about starting another crossover story so you're making me feel all warm and fuzzy.

Awkay, because stalling is never kind… Let's roll! I truly hope that you'll enjoy the ride.

The Return of Alyssa Stiles

/ Detective Damian Ennis, age thirty three, prepared himself for the worst when he was announced that there was a homicide case and a AMBER Alert. It only succeeded in making the whole thing more chilling that the murder place was a children's summer camp. While speeding towards the location he used all his willpower to not imagining what might be waiting.

Not that anything his imagination projected would've matched the reality.

The first thing he saw upon arriving to the scene was the body. A man in his late thirties with somewhat unruly brown hair and hazel eyes that were currently staring glazedly at the sky. Tall and clearly very athletic, definitely not the easiest possible target. Stabbed five times with a visible amount of determination. Someone really wanted the guy dead, then.

Crime scene investigator Garreth Jackson noticed him just then. The man straightened his relatively short form and walked to where he was waiting. On his way the investigator removed the head part of his entirely white uniform to allow him a visual to a bush of wild, blond hair. "You sure did get here fast." The younger man nodded towards the corpse, his green eyes grave. "That would be Trevor Durbin, one of the directors of the camp. He was killed sometime last night, most likely between one and three am."

Damian nodded, feeling a touch of something deeply unpleasant. He couldn't look away from the deceased's admittedly flawless face. "This is a kids' camp. Finding suspects isn't going to be pleasant", he sighed, feeling very tired all of a sudden. It took some time before he managed to find enough courage to voice the question burning his mind. "What about the missing girl?"

Garreth shook his head and shrugged, eyes darkening with dread and annoyance. "From what I've heard it's… bad." The investigator nodded towards the forest nearby. "A massive search party went there about an hour ago. There are cops, dogs and volunteers looking for her. At this point we can only wait."

Damian's eyes shifted ever so slightly. It wasn't until then he heard the distant rumble of a water fall. He wished he was surprised when another hour later the search party arrived with morose faces and a little girl's shoe that'd been found from the water fall's edge. /

Spencer's eyes were hazy and distant while he stared at the interrogation room's window, all too aware that he was sitting at the wrong side of the table. Outside raindrops kept crawling unnaturally slowly, like the course of time itself had been altered. To him it would've made sense that such might've happened when…

He took a deep breath, only then realizing that he'd been holding it. Repeated the action, for good measure, again and again until he felt dizzy. His lungs were burning, along with his eyes. The stinging in them hadn't disappeared since he saw the body. Her body.

"Reid." Derek's voice was soft, comforting. His scattered mind clung to it. "I know that this is hard, but… I need you to focus, okay? Because I need you to tell me everything you know about Maureen Stones, for her sake."

Hearing the name finally snapped Spencer fully to the present. He gritted his teeth, steeling himself, then unleashed the words. "Her name… It's not Maureen. It's… It was Alyssa Stiles." After letting the sharpest edge of the ache fade he went on. "I met her at a summer camp when I was… eight years old, I think."

Derek nodded slowly, making notes. For the first time since discovering the body their eyes met properly. The older agent gave him a look of deep sympathy. "What do you know about her?" the man inquired. "Why did she change her name?"

Spencer swallowed, unable to get rid of the horrible taste in his mouth. "I don't know much. I only knew her for about a month. Her parents were doctors, she had a sister."

Derek wrote all of that down, a frown deepening on the agent's face. "So… You never saw her again after that camp?"

Spencer shuddered violently, so much going through his system all at once that in became hard to breathe once more. His mouth opened several times before even the slightest bit of sound came. "No."

Derek had to notice that he was hiding something. But as it was the man seemed to let it slide. The relief was short lived. "Do you have any idea who might've killed her?" Now that was the million dollar question.

Spencer felt like he'd been shot. All the memories that flooded through him… The emotions they stirred… He wiped his eyes. "Yes." Yes, yes, yes, YES! His eyes were full of despair and his body was practically pulsating with sheer terror. Even the thought was impossible but… "There's… There was this man. But… I don't think that he's the one we're looking for."

Derek frowned. Confusion was loud and clear in the man's eyes. "Why's that?"

"Because he's dead." Spencer looked towards the window. The rain was falling harder. "And… So was Alyssa, even before tonight."

It was a early morning following a long, restless night and the agents approaching the apartment of a woman who turned out to be Alyssa Stiles were exhausted. That, and very worried. It was always taxing when a case turned out personal.

David was the one to break the somewhat tense silence. He rubbed his face a little while speaking, trying to wake himself up properly. "How is he doing?"

JJ glanced towards him with a quick blink, like someone who'd been on the verge of falling asleep. "Spence?" She averted her gaze, some pain flashing in her eyes. "Not… well. He's in a shock and seems to be grieving. Morgan's talking to him but I'm not sure how much he's able to tell right now."

David mulled over the information for a while before speaking again. His voice was a lot tighter than before. "Do you think that he's one of those two left the killer mentioned in that message?"

JJ shivered, feeling cold and sick to her stomach. "I don't know", she admitted quietly. And the honest, the bitter truth was that she didn't know anything anymore.

By then they were already steps away from the crime scene. David was about to say something more but the words died into the man's throat. Because they weren't alone.

There, standing unashamedly and boldly inside the police lines like he owned the place, was a tall man dressed in a long, black coat. The intruder's black hair billowed angrily in the wind that was still cold from the rain that lasted the entire night. He seemed to be examining something with a deep level of interest.

JJ and David exchanged a look, then began to approached with their guns fully ready. The stranger noticed them when they were four meters away. "I'd put the guns away if I were you", a deep voice rumbled.

David frowned. If anything his gun rose a little. "Why's that?"

To answer his question there was the unmistakable sound of a gun's safety being clicked off. "Put… them… away", a low, deadly voice came from behind them. There was a clearly apparent British accent. "Slowly. And make sure that I see your hands."

Anyone in their right mind would've obeyed that command. David and JJ put their weapons away slowly, neither daring to make any sudden movements. JJ's heart hammered furiously while she kept her eyes on the black haired man, trying to figure out what the hell was going on and how she'd get herself and David out of this mess.

There was a long moment of heavy silence until the tall Brit finally spoke, his face nonchalant despite everything that was going on. "Enough with the drama, John. It appears that these two are FBI-agents."

"What?!" There was movement behind them. "Bloody hell, Sherlock…! And it didn't even cross your mind to tell me that before I pulled a gun on them? I thought that they were going to shoot you!"

"You didn't exactly give me the time to explain, now did you?"

Seeing her opportunity JJ moved, mindful to do it slowly although it seemed that the danger was over. "I'm going to pull out my badge, alright?" Which she did, without earning a bullet to her skin. "I'm SSA Jennifer Jareau. The man beside me is SSA David Rossi. Yes, we're with the FBI."

"SSA?"

"Supervisory special agent", Sherlock supplied, beginning to sound impatient. Those sharp eyes were firmly on the agents. "You're investigating Alyssa Stiles' murder, correct?"

That was when David took a step forward. There was a disbelieving look on the man's face. "Look… Sherlock, right? And John. This is a crime scene. What…?"

"The same as you two. Solving a case." The man who was apparently called Sherlock lifted his chin, not a hint of hesitation or uncertainty in those eyes. "The name's Sherlock Holmes, the world's only consulting detective. And since you're questioning whether we should be here… Contact Mycroft Holmes from the British government. And do get to it quickly. We're wasting time."

In the end Spencer needed a break. Instinctively he headed towards the break room in hopes of finding coffee. It was nice to pretend, even if for just a moment, that caffeine would be able to erase the ghosts lingering on his tails.

He was just about to grab his fourth mug of the morning when he saw David approaching, appearing stunned, deeply annoyed and positively murderous. Spencer sighed inwardly. It wasn't too hard to deduce what happened.

Damnit, William…!

"JJ and I re-visited the crime scene", David announced in a dark tone. "And we weren't alone. There were two men. JJ's chatting with one of them, who claims to be a doctor and a former army medic. The other… He announced quite clearly that he'll only talk to you. In private."

Spencer nodded, trying to appear far calmer than he actually felt. "Okay. I'll talk to him." To be fully honest he wanted to talk to William, too. And preferably so that none of his teammates were there to hear. Some of the things that needed to be spoken through…

David frowned. There was worry and confusion in the man's eyes. "Are you sure that it's a good idea? You don't even know…"

"Actually… I do", he confessed and shifted his weight. Suddenly he felt quite uncomfortable in his own skin. "He probably told you that he's here to investigate the case but he's also a witness. Just like I am." Seeing David's stunned look and quickly parting lips he went on. "I'll explain later, I promise. But I need to see him first. Where is he?"

It was blatantly obvious that David didn't like it but the older agent also had very little choice over the matter when Spencer had made up his mind so firmly. They barely spoke while making their way towards the interrogation room holding William, both of them deep in thought. Spencer's heart was hammering at a speed that couldn't possibly be healthy.

Spencer hadn't actually met William since the camp. He didn't know what to expect. And then the door separating them was opened.

There, pacing around restlessly with energy that didn't seem to come from this world, was a tall man with wild raven hair and even more untamed eyes. Thin and pale by nature. In the few seconds that flashed by Spencer's eyes scanned through, trying to take in everything.

A former drug addict in a constant need of stimulation for his storming mind. Now worked to solve crimes. A chain smoker who'd grown quite skilled at hiding it. Very few close relationships. Severe trust issues, which was perhaps to be expected of a man who could see pretty much everything with a mere glance. Highly intelligent, deeply guarded, always insistent to gain the upper hand in every situation and every meeting. This time attempting to achieve that by staring him down. Most likely hadn't been able to rest properly in all his life, or at least since childhood. Which had left behind the restlessness, the constant need to be in motion, the never ending overdrive.

Spencer knew, with certainty that made him feel uncomfortable, that a similar evaluation was made on him by his counterpart and couldn't help wondering what the other saw.

In the end Spencer breathed in deep and took a step forward, wondering how to start. He didn't speak until the door was closed, partially because he wanted the privacy, partially because he simply couldn't produce a single word. "When I called you I was trying to warn you, not to invite you here. William…"

"It's Sherlock", the black haired man announced sharply. Those eyes doubled the weight of the words. "Don't ever call me William again."

Spencer nodded, sliding slowly to a chair that'd been placed to wait for him. "Okay", he amended somewhat numbly. "Sherlock, then." The man himself might've forgotten but he remembered, so clearly that it hurt, the kid that ferocious being used to be.

Spencer didn't quite know what to say but Sherlock clearly didn't have such a problem. The Brit's eyes were demanding as they kept staring at him. "You know a lot more than you've told your team. What are you hiding?"

A tremor crossed Spencer. Cold, terrifying in its power. His mouth went dry and it took considerable effort to regain his ability to speak. "I… wanted to talk to you first." He breathed. "How much do you remember of that summer?" He could see those shadows loud and clear in the other's eyes but he had to ask. Re-awakening those memories…

Sherlock's eyes were dark. A sudden might've mistaken them to be hostile. "I've deleted most of it." It was a somewhat wounded growl. A furious attempt to maintain control. "All I know is that after the summer when I met you and Alyssa she was dead, I didn't want to be called William ever again and I've been having nightmares of a man whose face I never see clearly." There was a pause during which they sized up one another. "I came here to solve Alyssa's second murder. And to get answers."

Spencer felt breathless, even dizzy. He swallowed, his sweating hands fisting and unclenching rapidly. "You should've stayed in England", he managed at last. "You should've let him stay in your nightmares instead of coming to face him again."

In the meantime Penelope Garcia was digging through the camp both Spencer and Alyssa participated. There wasn't much. Computers weren't exactly common back then, after all. But after a couple of phone calls to the right people she managed to get her hands on several pictures, a description of what was going to happen during the camp and a list of names of those involved.

Derek entered the room with the two mugs of coffee just when she was processing her findings so far. Her eyes had been drooping but they perked up instantly at the promise of caffeine. "My hero!" she sighed, accepting his offering.

Derek smiled, then nodded towards the pile that'd crawled its way to her desk. "What have you found so far? Anything important?"

If the circumstances had been a bit less grave Penelope would've smiled. "Guess what? The camp was designed for 'gifted children'."

One corner of Derek's lips twitched. "Why am I not surprised…", he mused. He leaned closer to read the documents and frowned. "Six weeks? Isn't that a bit long for children from the ages of eight to fifteen?"

Penelope nodded, not quite understanding the shivers going down her spine. "The children got the chance to visit home every weekend if they wanted to. Most of them did."

They studied the material in silence for a while until Derek saw something. The man's eyes widened a fraction. "That name Reid mentioned, Trevor Durbin… I just spotted it." He was pointing at the papers.

Not sure if she wanted to know Penelope took a look. She shivered. Trevor was one of the camp's directors.

Not knowing what to say she remained quiet, instead turned to her computer. In a moment a flood of information was right in front of her. "As far as I can tell he was a perfectly normal family man. A wife and three kids. No criminal record." The nausea from before rolled right back in when something in particular caught her eye. "He… died on the summer Reid was at the camp. Stabbed five times." Just like Alyssa.

Derek was quiet for a while, the same dread she was experiencing clearly going through him as well. It took a while before he managed to speak. "Where are his family members?"

Penelope did some searching. "His daughter died of overdose about a year ago and his other son moved to Europe in 2006. But his wife and other son live only an hour's drive away."

Derek nodded solemnly. "Good, in that case we'll pay them a visit. We've gotta find out what happened at that camp." Yet both of them were unsure whether they really wanted to know.

TBC

A/N: So your favorite geniuses have finally met. But oh, this is turning really, really murky. What in the world happened that summer? Who's the killer and the two targets left?

PLEASE, do leave a note before you go! It'd be awesome to hear from you.

Until next time, ya all! I really hope that I'll see you there.

Take care!

D. Rose: So the first chapter had you captivated, then? (grins radiantly from ear to ear with joy) GOSH, how I wish that the next bit will please you just as much.

Colossal thank yous for the review!