A/N: This was written for the Crossover Challenge, using Criminal Minds and CSI

12:15am- Las Vegas, Nevada

"Oh, now what!"

Las Vegas CSI Catherine Willows slammed a hand down on her dresser at the sound of her ringing phone. The shrill noise had pulled her out her a beautiful dream of a beach in Hawaii. Now, the woman was awake in her bed in the city of ½ million receiving a phone call, most likely from the only man who would call her on her night off- Gil Grissom.

Catherine lifted her head and placed it on her hand. Without checking the caller id, Catherine answered, "Gil, it better be life or death-"

"CSI Willows?" the voice on the other end replied. It was a female's, a loud yet tired female voice. Catherine pulled herself into a sitting position, deeply curious about the phone call. "This is she," Catherine answered.

"I apologize for the late night call, but this is urgent. My name is Erin Strauss and I'm the Section Chief of the Behavioral Analysis Unit within the FBI. We received a phone call from the mayor about the…Criss Cross killer as the media so crudely calls he or she."

Catherine scratched her head while mentally racking up all the information she could about the Criss Cross Killer. In her twenty plus years as a CSI, Catherine had never seen murders as grizzly as these. Twelve male victims- Hispanic and Asian with gang ties- had been found scattered throughout Las Vegas within the last seventeen months. Different methods of kill, different signatures, and multiple DNA affilials left at the scene had put the CSI Graveyard shift in a frenzy.

Strauss continued, "There's been word that this killer has crossed state lines from Nevada into Arizona. We'd like to work with you and any other CSIs that have worked on this case. Two of my agents and myself will be in Phoenix within a few hours. Your supervisor," there was a pause, "CSI Grissom said that along with you, there would be at least two other CSIs coming?"

Leave it to Grissom to be ten steps ahead of me. Pick two? How am I supposed to do that- everyone worked on this case! Catherine composed herself before stating, "Yes…CSI Nick Stokes and CSI Sara Sidle will be coming with me."

"Good. I'll be arriving with Agents Aaron Hotchner and Jennifer Jareau. See you soon."

And with that, Strauss hung up.

Leaving a very confused CSI sitting in disbelief on the other end.

3:45am- 600 Miles from Phoenix, Arizona

Erin Strauss bit her lip nervously as the jet glided towards storm clouds. According to the pilot, they were passing the very edges of a storm that was luckily not going to hit Phoenix. The Section Chief was happier about avoiding turbulence than anything else. It was one of the reasons, unknowing to everyone around her, that she didn't fly on cases- the woman was a nervous flier. None of the six profilers on the A team had the chance to figure it out as her trips on the jet were incredibly rare. However, the mayor of Phoenix was a personal friend who needed the case wrapped up quickly, which prompted Strauss to go.

Focus on something else, Strauss mentally told herself. She turned towards the opposite side of the jet where Hotch and JJ both sat with case files in their hands.

"Aaron, are there any updates from Quantico?" Strauss called out to the Unit Chief.

"No ma am. Garcia hasn't called back yet," Hotch replied. His tone was short and slightly bitter. Strauss already knew why: as FBI protocol, the Section Chief wasn't required to travel on cases, especially of this magnitude unless absolutely necessary. For this trip, however, she had insisted on only two agents going instead of the entire team, which forced the remaining members of the BAU's top team- David Rossi, Spencer Reid, Emily Prentiss, Derek Morgan, and Penelope Garcia- to stay behind in Quantico. In her mind, the smaller the amount of FBI presence, the most likely they would be able to catch the UNSUB. The Unit Chief, on the other hand, believed that a full team was needed to be the most efficient. After a long argument, Strauss pulled rank and won.

"Thank you. Since we've reviewed the case already….what do you guys usually do next?" Strauss asked. Hotch held out a blanket and said, "It's going to be a long day. You should get some rest."

"Thank you," Strauss answered. As expected, Hotch gave her a nod and returned back to spot without a word. Strauss sighed and turned her attention back to the window. Two pissed agents, she thought, my third trip out in the field, and the BAU's first experience with CSIs of this caliber- I really hope this goes well.

4:15am- Phoenix Sky Harbor International Airport

"Erin, nice to see ya again!" Phoenix mayor Jennifer Harlow greeted in a bright tone. The woman had just run into Strauss five minutes after the team's flight landed. Strauss shook Mayor Harlow's hand and replied, "It's great to see you too, Jennifer. Thanks for calling."

"Your team is one of the best and the Phoenix area is out of options. No offence, though, I thought I'd be getting a full deck here, not two agents," the mayor replied. She shook Hotch and JJ's hand before focusing back on Strauss. "We're going to have you at the city hall for precaution. The media's already flooding the police station."

"How bad?" JJ asked.

"Pretty bad. CNN and a few local guys have set up camps outside the station. "

Hotch added, "That's normal for this type of situation. We need to get complete control- there is a possibility that our UNSUB's behavior could be influenced by the news."

"Good. I'll try and get in contact with them. " Mayor Harlow answered. She started walking towards a tinted window black SUV that sat in front of the terminal. "You can meet the CSI team from Las Vegas at Meadow Park within the hour."

5:20- Meadow Park- Phoenix, Arizona

"Hey, Cath. We haven't heard much about this BAU team that we'll be working with," CSI Nick Stokes mentioned to Catherine. Along with CSI Sara Sidle, the three CSIs were standing in the middle of an empty field where Phoenix police thought the Criss Cross killer had chosen for his new body dumping site.

"Not much I can tell you, Nicky," the blonde CSI answered, "They analyze behavior."

"Hmmm, Grissom would have loved to see this."

"Tell me about it." Catherine was getting impatient, no doubt in her mind that the younger CSIs were feeling it as well.

They had arrived from Las Vegas thirty minutes prior, alert and ready to work. Before they could get the chance to explore the crime scenes, the mayor had insisted that they wait for the BAU.

And with a serial killer out there, it was hard for three CSIs from the country's second best lab to sit around and wait.

"I don't know how much longer I can wait," Sara groaned. She shifted the weight between her feet, which caused her boots to sink into the ground. Catherine smiled at the younger CSI's misfortune before she noticed a dark SUV approaching the park. The SUV came to a halt a few meters away and the two agents and Strauss stepped out.

"Are you Catherine Willows?" Strauss asked. Catherine held up a hand and replied, "Yep, that's me. You must be Erin Strauss. "

Strauss held out her hand. "Yes, it's a pleasure to meet you. These are Agents Hotchner and Jareau."

Catherine shook both Hotch's and JJ's hands before pointing back to Nick and Sara. "Yes. This is CSI Nick Stokes and CSI Sara Sidle, my team members. Let's get to work."

Nick pointed to the horizon where the sun was slowly rising. The slight orange hue highlighted the meadow peek. "We need to get a head start on looking-"

"Looking for what?" JJ interrupted, "The crime scenes were preserved, right?"

Nick pulled out a map of the park and laid across the front hood of the SUV. He pointed to the northern sector where someone had marked a large X. "Before we left Vegas, someone had dropped this map off at our station with a note saying that it was related to the Criss Cross killer. The X is right where Phoenix PD think the new burial site is. It's best we check it out now."

"He's right," Hotch directed, "We can spread out a half mile in groups of three-"

Catherine cut Hotch off, "Two will be faster."

"We don't know what's out there," Hotch replied irritably.

"Well, my CSIs and I along with you are all prepared. Agent Hotchner, we should be ok."

Not all of us, Strauss thought nervously. Before she could open her mouth to protest, the CSIs and agents had split up- JJ and Sara were grabbing flashlights from the back of the LVPD rented SUV and Hotch and Nick were already walking out in the field. Strauss hesitated before looking over to Catherine, who was checking her walkie talkie.

"Let's get to it," Strauss stammered. Catherine nodded and started walking west from the SUV. The Section Chief awkwardly followed her, taking every chance she could to look behind her. A few minutes of silence went by before Catherine suddenly stopped and asked Strauss, "Are you ok?"

"Yeah- yeah, I'm fine," Strauss lied. The eerie quite coming from the tall grass was making her skin crawl.

"…Ok." Catherine started walking again and headed deeper into the park. At every sound of crickets or owls, Strauss fought down the deep urge to scream out for Hotch and JJ or to run back to the SUV.

Whooooooo…..

"Whoa, what the hell was that?" Strauss screamed at the sound of noise coming from a large bush in front of them.

Catherine immediately drew her weapon and shooed Strauss. Both women froze in their places while expecting a large animal or even a killer to step out from behind the bush. A breeze blew by, revealing nothing but a small rabbit. Catherine dropped her arms down and exclaimed, "Seriously? How are you in the FBI?"

Strauss brushed down her blouse while trying to catch her breath. "I…..am a bureaucrat- not an agent."

"And what? There were only two free agents that you had available for this case?"

"No-no, but I wanted to be here for this!" Strauss exclaimed. She stopped herself and caught her breath.

Catherine crossed her arms, expecting an explanation. "Chief Strauss, I barely know you, but I can't work with someone whose mind isn't this game so I have to ask," Catherine said, "What's going on with you?"

"I feel so weird saying this, but…..I'm a bureaucrat, but I need to get out of my office and get out there, you know. There was a case that happened in May in the capital and….it was frightening. A bank blew up and the A team almost lost a loved one. I guess I just want to be more prepared- braver, you know out in the field. I think something in me cracked after that case. I just want to be brave- I know it sounds corny."

"I see." Catherine pulled up a sleeve, which revealed a thin, red scar near her elbow. She said, "My team is known for getting in a lot of dangerous cases. Chief Strauss, you don't have to force yourself out in the field to see if you can handle cases. You just have to ignore it, ma am. You survived that case and that's all that matters."

Strauss chuckled softly at Catherine's words. The bank robbery was so frightening to her- she had spent days wondering how Agent Jareau went on to get married a few hours after or Agents Morgan and Prentiss went to the US Virgin Islands the next day. For years, she had sat behind her desk wondering what the trick was for beating Tobias Hankel, George Foyet, or Ian Doyle when the answer was so simple. When the time was right, she could go out into the field and develop the same skills that the agents had, but until then; it was best that the Section Chief would go where she was needed- her office.

"Thank you, Miss Willows. That helped a lot. I think the best thing for me to do right now would be to get the A team down here ASAP."

"Good, but since you're here," Catherine reached into her case and pulled out a stripped Taser, " let's use this opportunity and get you some field work so that when you come to the next….I don't know, bank robbery, you'll be a little more confident. Sound good?"

Strauss took the Taser in hand and admired it slowly. She then looked up and smiled brightly. "Thank you," she told Catherine.

"No problem," Catherine answered as she picked up her case and started walking again, "No problem at all."

The End