"Okay, the chair didn't end up the same way as at the scene, with that scenario." Warrick said.

"Nor did our vic."

"So we want to get our vic like this." Warrick moved the dummy. "And the chair to fall in this direction." He upset the chair.

"That's easy." Sara said seeing how he'd set it up as she entered the garage.

"Sara." Warrick said. "What were you saying?"

"It's easy to make a wheelchair fall that way and tip someone out." Sara said.

"How do you know that?" Nick inquired.

"I may have gone to a few wheelchair races."

"Wheelchairs races?" Nick questioned.

"One of the fraternities when I was in college used to misappropriate wheelchairs from the med school and have wheelchair races. Sprints, manoeuvrability around obstacles, they did that one blindfolded and then they have a competition to see who could tip their wheelchair over in the most creative way."

"You went to wheelchair races?" Warrick questioned.

"I thought you didn't like fraternities?" Nick added.

"I don't like fraternities or sororities but I liked the physics behind the wheelchair races. Given how screwed up my family is science is the one thing that always made sense. But that wasn't why I'm here."

"I just thought you were taking a breather from Greg." Warrick stated.

"He went back to the Bellagio to get the security camera tapes for the lobby. I went and got my tox results yours were ready too so I grabbed them. Your vic was too doped up to roll herself anywhere; she had to have been given a helping hand." She handed the file to Warrick.

"Thanks. I guess we're going back to Sunnyview." Warrick told Nick.

"I've got to go and find Catherine so I'll see you later."

"Hey Sara." Nick called after as she started to leave.

"Yes?" Sara turned around.

"How do you get the chair to fall like that?"

"Here hold this." She walked back and handed him the file with her tox results in. Warrick helped her set up the chair again with the dummy in it.

Sara positioned the chair at an angle with the handles facing away from her and gave the wheels a sharp push, the chair bounced off the fake wall they had set up, the dummy fell out and the chair fell over in almost exactly the same position as in the photographs.

"Print the wheel rims." Sara said taking the file back from Nick.

"Guess you do learn something new everyday." Warrick said as she was gone. "Do you know what she was talking about with her family?"

"Don't spread it around but Sara's parents were hippies and her father was pretty abusive towards her mother. In the end it got too much for her and she stabbed him to death."

"Sara's Mom killed her father?" Warrick repeated.

"Sara and her brother spent a good ten years kicking around the foster care system."

"And she got into Harvard?" Warrick questioned.

"You know Sara; she can pretty much do anything she puts her mind too. She worked hard and got a full scholarship. It's why some cases hit her harder than others."

"How did I not know about this? How did you know about this?"

"A little too much tequila after a bad day." Nick replied. Recalling the conversation which had also led to his confession about the last minute babysitter. "Don't say anything to anyone, she doesn't want people knowing."

"Does anyone else in the lab know?"

"Grissom might but I doubt it." He paused. "I'll go and print the wheelchair rims."

"I'll check in with the doc and then I'll come and find you."

"Okay."

CSI CSI CSI

"Catherine." Sara said when she located her.

"I just got back from talking to Doc Robbins official cause of death exsanguination. The cut nick the heart and several other major organs. He didn't stand a chance."

"Tox report shows a high blood alcohol level. Security cameras were blacked out when our killer entered and exited the elevator and the ones in the hallway to our vic's room. Greg's gone back to get the lobby footage so Archie can see if he find anything on there. But we have no useable prints from the room or the murder weapon."

"So we're stalled. We need to call Brass and see if we can get a little more information on why our vic was in town." Catherine stated.

"Do you want to call him? Or should I?"

"I'll call him." Catherine said pulling out her cell phone.

"I'll go and see how Mia's doing in DNA."

"Sara are you ever going to tell us who he is?"

"You'll figure it out. But one more clue since Archie figured it out already. He works in this building."

"Grissom?" Catherine questioned.

"I got over that a long time ago." Sara replied. "Call Brass."

TBC