Title: In The Deep Abyss

Full Summary: A crossover between Criminal Minds and The X-Files, set during Season 7 of Criminal Minds, set between Snake Eyes and Closing Time, set during the Season 10 continuation of The X-Files. When mutilated bodies wash ashore in a small town in California, the BAU is called in to stop the UnSub before more victims are claimed, things become complicated however when two newly reinstated agents are brought into the investigation at the same time. Methods clash, truths uncovered, and a killer the likes of which had only existed in legend.

Big Bear Lake, California

Teenagers in love, it was an innocent sight at the most. They were locals well on their way to being the kind of high school couple who'd marry...their fates were the last on their minds as they made their way to the famed lake, not too far from the home of one of the two. The moonlight shining on the figures of an average height male, his hair as black as the night, running towards the water, the other figure being a female just a few inches shorter than him, her wavy blonde hair picked up by the moonlight. Following her boyfriend toward the waterfront, the feet of the two silently smacking against the dirt, the silence of feet against the dirt turning into the smaller sounds of bare skin smacking against the rocky edge while making their way towards the water. The two standing at the edge before jumping in, a loud simultaneous splash being made as the two plunged beneath the calm waters on the enchanted evening. The two finally rising to embrace in a brief kiss.

"I'm glad you talked me into this." The girl said with a smile.

"And you said you didn't wanna?" The boy replied, feeling his girlfriend wrap around him.

"Well, it's night and this particular area has all sorts of nasty little critters."

"Those nasty little critters live on land, darling."

"Whatever." she giggled "As long as they stay away from me."

As the lovers enjoyed their moment of peace together, there was the undeniable fact they were not alone, being trailed by a figure, lurking in the woods. The "nasty critters" being the least of the issues as it'd watched them from the far, slowly entering the water, submerging into the depths of the lakes waters. The figure staying down as long as they were able to before having to resurface for air, making sure when they did so, they were far away from the two and as quiet as possible. The two lovers seemed to not notice anything from the figure, stalking, watching, as if they were prey. And the stranger was the hunter. Hungry to make the kill.

"D'you hear that?" The girl asked, her lovefest distracted by the sound of something landing on a nearby rock formation amongst many on the lake.

The boy looked around, much like his girlfriend "I heard it but..maybe it's nothing." He said, his girlfriend detaching herself from him "Maybe it's just some old fisherman, people fish here and all."

"I'm gonna head back to land." She said, swimming away from the boyfriend and heading back to the shoreline.

"Babe, c'mon, wait." The boy said, following his girlfriend, instantly stopping however when he felt a sensation of something brushing against him.

"Forget it, I don't wanna be watched by some perv." She replied, looking back at him "What is it?"

"I felt something like, move against me."

"Dude, no."

"What?"

"You're trying to scare me now, asshole."

As the boy tried swimming towards his girlfriend, he felt as if he were...stuck, in the middle of the water, suddenly submerging all his own, it didn't take long for the girlfriend to notice "C'mon, we're not doing the Jaws thing again, are we?" she aked, swimming back to where he'd disappeared. Waiting for him to resurface so they could get it done with and be on their way "C'mon Curt, not funny." She said, looking around, nothing but the shore and the moonlight shining on the water's surface, as she searched for her boyfriend she felt a brushing sensation against her, it stopped being simply something brushing against her and soon became something that was pulling her down to the waters depths, her attempt to hold her breath. Eventually grasping for air as she saw how further and further to the bottom of the water she was being lowered too. The fear running through her right now was the kind you'd find in a nightmare, a nightmare was what she was hoping this would all turn out to be and when she woke up, back in her bed or in her boyfriend's car, this however would not be the fate she'd hoped for, it ended up being the exact opposite. It was her sad reality that she was pulled down to a most horrifying death...

48 Hours Later

Quantico, Virginia

After the incident in Big Bear Lake, it came out that another similar incident had occurred on the land. The current idea being that a serial killer was running around Big Bear Lake, running around and causing the damage and deaths in the area. This case became the attention grabber of the BAU, it was not often that bizarre often strange murders became a thing of their attention. The prime objective now being who the suspect was and how to bring them to justice, the team had been assembeled to go over the case details, the nature of the deaths.

"Alright my pretties, Big Bear Lake is the center of a new mystery." Said BAU technical anylast Penelope Garcia "This is 18 year old Curt Adams, local school athlete and girlfriend, 18 year old Marissa Bame were found washed ashore." She said, showing the faces of the victims to the rest of the team "And when found they were both...just...god." She said, clicking to zoom in on the state of their bodies "These are two eviscarated teenagers, not the only ones either a group of four campers in the San Bernardino National Forest, not too far from the lake were found ripped apart the exact same way."

"We're looking at a spree killer then?" Asked agent David Rossi.

"If the UnSub is a spree killer then he's got one hell of an MO." Replied BAU agent Derek Morgan "These bodies look like they were bitten into."

"That's because, according to autopsy done on the bodies of Curt and Marissa, there were teeth marks and I mean these teeth were sharp." Garcia replied.

"So, we're looking for a spree killer with cannibalistic behavior?" Asked agent Emily Prentiss, the murders being confusing and...strange, even for the killers they've dealt with in the past.

"If the UnSub's a cannibal then there might be a ritualistic reason for it." said Dr. Spencer Reid "The consuming of human flesh has been recorded quite a bit throughout human history, most notably it was a practice of the ancient Aztecs and Mayans as part of sacrifices to their gods in exchange for good weather, bountiful harvest."

"Then what's the killer going for in this case if it's sacrificial?" Asked agent Jennifer "JJ" Jareau

"Could be for luck, money, power, women, sex. It was believed that sacrifices meant that the gods would bestow upon anything that the person had asked for, but in all the legends the Mayan or Aztec gods would add a little twist to their deal." Reid answered.

"These deaths get weirder, while the campers were killed on land, Curt and Marissa showed signs of being drowned in the water." Garcia interjected.

"Were they able to determine if the evisceration took place pre or post-mortem?" Morgan asked.

"From what the autopsies of Curt could tell, the ripping of him to pieces took place post-mortem, as such they've presumed the same had happened to Melissa as well."

"Those teenagers must've been seen as a challenge by the UnSub." Prentiss theorized "I mean, he or she knew that one of them was an athelete, and probably saw doing the same to the girl was just a precaution."

"Hey, if I can ask, where's Hotch?" Reid asked, noticing the absence of unit chief Aaron Hotchner.

"He said something about Strauss calling him to her office, she's been keeping hush hush about the whole thing." Prentiess replied, telling all she exactly knew about the whereabouts of agent Hotchner.

"That can't be good." Rossi said.

Within a few seconds the door to the BAU's conference room opened, Hotch entering the door and closing it behind him "Garcia have you filled the rest of the team in on the case?" Hotch asked.

Garcia nodded "I have, and I gotta say, this is one of crazier ones we've seen."

"Hotch, what did Strauss call you in to talk to her about?" Rossi asked, genuinely curious about what the two had been talking about.

"Of course." Hotch said, looking at the entirety of his team "Strauss told me earlier today that two agents had been sent in from DC to assist in the Big Bear Lake murder case." Hotch said beginning to explain the nature of his conversation in Strauss' office.

"Agents from DC?" Morgan asked.

"Define well known." Prentiss said.

"A few years ago a division of the FBI had been shut down, the cases being shelved by the bureau and classified as unsolved." Hotch continued "Word came from DC that what's happening in California might be up the alley of these two...recently reinstated agents." He said "Believe me when I say I wasn't expecting them to be brought into this investigation either." He paused for a minute.

"C'mon Hotch, who are they?" Morgan asked.

"It is with pleasure." He said, opening the door slowly "That I introduce to you all, special agents Fox Mulder and Dana Scully." He said, the door fully opening to reveal the two agents "Of the X-Files division."

"No way." Reid said, it was without doubt the Mulder and Scully had quite the reputation.

"The Mulder and Scully?" Prentiss asked, even seeing the two enter the BAU conference room, it was sorta that thing you never expect.

"I don't believe it." Morgan said.

"If we're done here?" Rossi asked "So, what makes the Big Bear Lake killings related to your division?" He inquired, Rossi was curious about the involvement of Mulder and Scully.

"Well." Mulder said "Now that you mention it, agent Rossi, a similar pattern of killings happened not too long ago just off the coast of Fort Lauderdale, then again in Corpus Christi, now it seems that whoever is behind this is able to disappear without any trace...and unlike the campers in Big Bear Lake, it looks like the killer spent all of their time in the waters." He added.

"We were also told that we were to head to Quantico to work with the BAU on this investigation." Scully said "We're pleased to meet all of you as well, can't say I haven't heard my fair share of things about you." She smiled.

"I'd suggest you all get to know each other, I have something to deal with in the mean time." Hotch said, leaving the room.

As Hotch left the BAU conference room for his team and the X-Files unit duo to become more well acquainted he entered the office of BAU section cheif Erin Strauss, the one who'd told him about Mulder and Scully being sent to work with his team "Everyone seems to be taking the news well." Hotch said, closing the door to Strauss' office behind him.

"I'm glad." Strauss replied "Agent Hotchner, I want you to do me a favor while you're out in California."

"What would that be?" Hotch asked.

"Keep an eye on Agent Mulder." Strauss answered.

"Excuse me?"

"Agent Mulder has a...reputation in case you haven't forgotten."

"I'm well aware of the incidents involving Agent Mulder."

"Agent Hotchner, you know I was reluctant to let them be involved with this case, however it was felt that their presence was needed."

"I understand."

"Glad to hear it, in the meantime, your team and Agents Mulder and Scully have a plane to catch."

With that, Hotch left Strauss office. It was no secret that Mulder's methods weren't looked well upon by members of the FBI's higher ups, multiple times his division had been shut down due to the incidents that had been caused, re-entering the conference room "Now that we've got everything in order." Hotch said "Wheels up in 30, San Bernardino County sheriff's office wants us in Big Bear Lake asap."

The 30 minutes had passed, the BAU jet taking off for California to investigate the killings in Big Bear Lake, the seating arrangements made to fit the two additions to the investigation. It wasn't long before the jet was high above the sky, on it's way to the golden state to find who was responsible for the murders of Curt Adams, Marrissa Bame and the four other campers who were found dead as a result of the UnSub running around town.

"So, the MO is consistent with the Tampa bay murders and the Corpus Christi deaths." Scully said, looking at the photos from the crime scene in California, looking to her side, Mulder having been quiet for some time "Something wrong?"

"No, it's just..." Mulder paused looking out the window of the jet "How come we didn't get our own plane to take us to our investigations?"

"Really Mulder?"

"Yes, really, I'd kill for a jet for us." He said "Beats having to deal with the usual screams, hollers and general rudeness on the planes we've been on."

Scully smiled "Maybe we should talk to Skinner-I mean, Morales about that." She said, forgetting briefly for a second their new A.D.

"Think she'd go for it?"

"Maybe."

"Hey, Rossi, I thought you were retired?" Mulder asked, looking from the jet window to Rossi.

"I did, then I came back after 10 years, why? you read some of my books?" He asked.

"Me? No." Mulder answered "Her?" He nodded to the redhead "Yeah."

"If we can focus on the UnSub here?" Morgan asked, looking at the crime scene photos.

"Of course." Mulder said.

"Drowning victims, takes a while for them to die." JJ said "Think the UnSub's a sadist as well?"

"Or they were desperate." Reid suggested.

"Desperate?" Scully asked.

"Well, possibly because the drowning of victims does indeed take longer, it might've been that since the UnSub is most likely a spree killer and they didn't want a witness so they went with taking them both."

"That must've been a hell of a killing method." Morgan said.

"How do you think he was able to sneak up on both?" Hotch asked.

"More than likely was watching them for a period of time." Reid suggested.

"If that's the case then that says the UnSub is patient." Mulder said

"And the idea that they're cannibalistic." Prentiss said.

"Also the fact that the killer's victims are both male and female, so we know they have no preferences in regards to gender." Scully said.

"What bugs me about calling him a spree killer though is the UnSub seems to kill using sharp tools, not a gun, I mean it's basically a trademark of theirs." Reid said.

"Could be the UnSub believes that using a gun to kill his victims is ineffective and considering how Big Bear Lake is not say Los Angeles where gunshots are frequent." Mulder replied.

"That could be a major factor." Rossi replied "Although I'm not sure why they'd go to a smaller area like Big Bear Lke and not say San Bernardino."

"The UnSub probably finds the rural area is a better hunting ground, and a better hiding place." Prentiss said.

"What about the possibility the UnSub is a combination of spree killer and thrill killer?" Scully asked.

"There have been a few spree/thrill killer combinations." JJ said.

"The Mulford Family for example." Reid said

"Sound like wonderful people." Mulder deadpanned.

"So, we have a spree/thrill killer combo who indulges in cannibalism." Morgan said.

As the group discussed the pathology of the UnSub running around in Big Bear Lake, California. It couldn't be helped that Mulder thought to himself, maybe the UnSub has some other motivation aside from cannibalistic urges or even the thrill of killing people, he wasn't exactly sure what that deeper motivation was but he was sure that as time went on in their investigation the clues would be coming out of the wood work more and more. It was still a few more hours though before they were going to land .

To Be Continued

A/N: To my readers, this was a project I had been working on for a while now. And as for my Supernatural fanfic Crossroads? I apologize for the long wait, there has been trouble getting things together because of computer issues.