A/N: Hey guys! It's been a while since I updated the story. I knew I told you I would do it during my vacations (by the way, I'm still on vacations since I don't start collage 'til September), but life gets in the way. I had this idea for a new fanfic so I couldn't write the chapter until I started to write the other fanfic and then, a tragedy came into my family...my dad passed away a month ago, so I'm still dealing with the grief 'cause it was so suddenly, but you know we need to move on. I apologize if the chapter seems off. I hope you enjoy it!

Chapter 12: The Ace Killer, part one.

Once Greg was secure with a bullet-proof vest, Mac gave again the information about the undercover operation. He emphasized the fact that they needed to capture the Ace Killer alive to interrogate him.

"Okay, each one of you knows your position, stay there even if the Ace Killer gets away." Mac said.

"Flack, you and other detectives will be near the main entrance of the park. Danny, Lindsay you'll be among the crowd. Greg, Morgan; you'll be sitting over those tables and Jo, D.B. and I will be near the place where Owen will meet the Ace Killer." He said. "And Sheldon and Adam are in a mobile unit, they will help us with video and audio and will record everything the Ace Killer and Owen talk about."

The team nodded in agreement and they left for their positions. Mac gave the sign and some detectives brought Owen and left him a couple of meters away from the bench where he was supposed to meet the Ace Killer.

"Okay, everyone report in." Mac said through the microphone.

"Team one in position." Flack replied.

"Team two in position." Danny said while he and Lindsay were walking through the crowd.

"Team three in position." Morgan said while she and Greg were sitting at the table.

"Adam, Sheldon; how's everything there?" Mac asked.

"We have complete view on you and Owen's microphone works good." Adam said.

"As soon as the Ace Killer appears, we'll run the facial recognition program to see if he has any criminal records, maybe we can finally have a name for our Killer." Sheldon said.

"Okay, thanks Sheldon." Mac said and the teams waited for the killer.

While they were waiting for the Ace Killer, Morgan and Greg decided to order something to drink to make it seem like they were on a date. Morgan glanced at Greg and saw a sad look in his eyes.

"Hey, are you fine?" She asked.

"Hmm? Oh, yeah. Sorry." Greg said.

"Are you sure?" She asked.

"Yes. Well, you know, if someone has been stalking you for the years and is planning to kill you or harm you in a way at least you'll like to know name." He answered.

"You're right." Morgan said. "Have you talked to Nick?" She asked.

"Yeah, Nick asked me how I was and I told him that I was bored for staying too long in the hotel room." Greg said with a hint of sarcasm.

Morgan chuckled. "Also your dad called me." He said.

Morgan looked surprised. "He did?" She asked.

Greg nodded. "Yeah, actually I was surprised." He said.

"I never thought my dad would do something like that." Morgan said. Both of them started to laugh. The minutes passed and every time someone approached to Owen they waited if they sat next to him and started to talk with him, but there was no luck.

After a while, Adam and Hawkes saw a man using sunglasses and a blue sweatshirt. "Mac, we see a man using sunglasses and a blue sweatshirt." Hawkes said.

"Sunglasses at this hour?" Russell asked confused.

"It might be the killer." Mac answered. "Sheldon, where is he?" He asked.

"He's north of your position. Flack do you see him?" Adam said.

"Yeah, okay everyone keep an eye on him." Flack said to the other teams.

"We see him." Danny said.

"We see him too." Morgan said.

"Remember, don't let him see you. He doesn't have to know there are cops here, we need him alive." Mac said.

The Ace Killer approached to Owen and sat next to him on the bench. "I'm glad you came." He said.

"You think I wouldn't?" Owen asked.

The Ace Killer laughed. "We both know the reason you came:" He said and Owen looked afraid. "So you could still be a free man." The Ace Killer said.

"So, why did you ask me to see us here?" Owen asked a couple of minutes later.

"I have a new target for you." The Killer said. "Actually, two targets for you." He said and gave Owen a yellow envelope.

Owen took the envelope and opened it, he took whatever was inside. "What did he gave him?" Hawkes asked while looking at the screen.

"I don't know, let me ser if I can zoom the imagen." Adam said and he did it and also he improved the imagen. "Two photos, one of Gregand the other...I don't who is he." Adam said.

"Mac, the Killer gave Owen two photos. One is from Greg and the other of our last suspect." Hawkes said.

"Copy that Hawkes. Keep listening." Mac said.

The Killer and Owen continued talking for a while when the Killed glanced at the direction where Greg and Morgan were sitting. The Killer recognized Greg, so he turned to Owen.

"You brought the police!?" He said very angry.

"What? No." Owen said.

"Mac, we have a problem." Hawkes said.

"We see it." Mac said. "Flack, stay in position until I say otherwise." He said.

"Copy that Mac." Flack said.

"Danny, Lindsay. Stay in position." Mac said.

"Copy Mac." Danny said and he and Lindsay walked to the bench.

"I knew you were a coward." The Killer said and saw all the undercover detectives walking towards them. He thought fast and punched Owen right in the face and run off.

"He's on the move!" Mac said and all the detectives started to run after the Killer. Mac, Danny, Flack and Greg chased the Killer while the other ones stayed with Owen. They chased him through the festival avoiding to collide with the people and through the park until the Killer turn left and dissappeared after climbing a wall.

The three detectives and the CSI from Las Vegas stopped in front of the wall. "Where is he?" Flack asked.

"I don't know." Mac said. "Adam, Hawkes. Do you see him?" He asked.

"No." Adam said. "We lost visual on the suspect." He said.

Mac and the team was frustated. They almost had the Killer and he ran away. "I want Owen to be processed and this part of the park." Mac said upset. "If he left something, we will find him."

The team started to look for any trace the Killer had left behind. While Flack and his detectives were asking for witnesses, Mac and his team looked for evidence, fortunately, one of them found the sweatshirt the Killer had used and took it to the lab. After finding small evidence, the team was ready to return to the lab, except for Greg who was sent back to his hotel room.

The rest of the team arrived at the lab and started to process the evidence they had found. Sheldon processed the sweatshirt and he found hairs on it, so he took one of them and started to analyze it. Meanwhile, Danny had found the sunglasses the Killer had use and he looked for any traces of sweat that could contain the Killer's DNA.

"Sheldon, you have something about the sweatshirt?" Mac asked.

"Yes, I found short hairs on it, I took a sample. Let's hope we have a match in the system." Sheldon said.

"Call me when you have something." Mac said and Sheldon nodded.

"Hey Mac." Danny said from the Trace lab.

"You have something?" Mac asked.

"I didn't find sweat on the sunglasses the Killer left behind, but I did find partial fingertips, I'm running now through the system." Danny said.

"Good, call me when you have the results." Mac said.

Meanwhile, Greg was sitting in the lobby of the hotel when someone sat in the couch across him. "Hey Greg." Jerome said.

"Hi Jerome." He said.

"Did you know if they found the killer?" Jerome asked.

"Sorry, I can't tell you even if I'm out of the case." Greg answered.

"Oh, okay." Jerome said. "I met with someone after the NYPD released me." Jerome said.

"Who?" Greg asked looking at his friend.

"Mark." Jerome said. Greg was surprised. He hadn't heard from his childhood friend since that tragic night.

"Where?" Greg asked.

"Outside the building where I live." Jerome said. "I was very surprised when I saw him."

"What did he tell you?"

"Not much, he said he wanted to talk with the two of us and I told him you were here." Jerome said. "And since you're out of the case, you have time for us, right?"

Greg was a little surprised for this but Jerome was right, since he was out of the case he didn't do much in the hotel room, only waiting for Morgan's call to telling him how the case was going. "Yeah, sure." Greg said.

Jerome smiled. "It will be just like old times." He said and the two left the hotel.

"Taylor." Mac said answering his phone.

"Mac, it's Hawkes. I have the results of the hairs I found on the sweatshirt." Sheldon said.

"I'm on my way." Mac said and hung up the phone. While he was on his way to DNA, Russell saw him. "Yeah, okay. Thank you, Nick. I'll keep you posted." He said hanging up the phone.

"Mac!" He said catching up with the detective. "Where are you going?"

"DNA. Sheldon found a match with the hairs found on the sweatshirt the Killer was wearing." Mac answered as he and Russell walked into DNA.

"The DNA I took from the hairs is in the system." Sheldon said as he hold a folder in his hands.

"We have a name?" Mac asked.

"Yep, but our victim's DNA appeared in Missing People." Sheldon said.

Mac and Russell stared at Hawkes with confused looks on their faces. "The victim's name is William Anderson, he was reported missing when he was 14." Sheldon said.

"Where did he lived?" Mac asked.

"His family moved to Baltimore when he was nine, a few years later he dissappeared and his parents reported his dissapearence to the police. Flack is talking to the Baltimore PD to know all the details of the case." Sheldon said.

"Do you have his background information?" Rusell asked.

Sheldon shook his head. "Flack said he's going to send the information once he talks with the Baltimore police department." He said.

"Mark!" Greg said when he saw his friend.

"Greg! How are you?" Mark asked while hugging Greg.

"I'm fine. And you?" Greg said.

"Well, you know. Life is always moving and we can't stay back." Mark answered.

"How's your old man?" Greg asked.

"He's fine. Jerry told me you are a criminalist." Mark said.

Greg smiled. He missed talking with his old friends like this. "Yeah, I used to be the DNA technician but after a lot of work and effort, I was able to do field work." He answered.

The other two laughed. "They, I heard you wrote a book about the history of Las Vegas." Jerome said.

Greg blushed slightly. "Yeah, the city is full of secrets." He said.

The three of them laughed and started to order different kind of drinks and continued talking about the past days. Meanwhile, Mac was reading the information Flack had sent him after talking with the Baltimore police. He read the files until something got his attention; he got up and looked for Russell.

After a few drinks, Greg and his friends were still talking about their high school days. He smiled at the old memories when everything was fine, they continued talking and drinking for a little while.

"Are you sure he returned to the hotel?" Russell asked.

Morgan nodded. "Yes, I accompanied the officers who took him back to the hotel." She said worried. They had tried to speak with Greg about twenty minutes ago, but he didn't answer his cellphone and the hotel's phone of his room.

"Any luck?" Mac asked. Russell shook his head. Mac sighed. "D. B. go with Danny to the hotel and see if you can find anything that tells you where he could be." He said.

Russell nodded and he left with Danny the crime lab and went to the hotel. Morgan sighed tiredly; she only wanted to know if Greg was fine.

"Shure you don't want to come?" Jerome asked drunk.

Greg shook his head; thankfully he was only dizzy after the two shoots he had taken. But right now, Jerome and Mark decided to go to another bar and they asked Greg if he wanted to come along but he said no.

"I guess I'll stay here a little while, you guys go and have fun." He said.

"Okay, see you later!" Mark said and he and Jerome left the bar. Greg stayed for ten minutes more and then he decided to return to the hotel. He paid his bill and left the bar. He never knew that someone was waiting for him outside the bar, so when Greg exited the bar, that someone hit him with an empty bottle.

The last thing Greg knew was that someone was walking towards them and after that, everything went black.

To be continued…