Catherine and Grissom followed Greg down the immaculate central hallway of the lab. A passing receptionist's three-inch heels tapped out a satisfying click-click on the polished floor, the syncopated rhythm matched the expectant and excited beating of their hearts. With an exaggerated flourish, Greg showed them into the DNA lab. He ran a shaking hand through his spiky hair, and both Catherine and Grissom noticed this startling change in their friend's demeanor.
"What's up Greg?" Catherine asked, her brow knit in confusion and worry.
"I ran the contents of the box you brought in from Sara's closet. It's not good, guys."
"What is it?" Grissom asked impatiently.
"Some of the underwear had DNA evidence on them. There was semen, but it was almost all pre-ejaculate. This guy knew what he was doing. No viable DNA matches could be made from that."
Catherine interrupted, "You said almost. Did you get a match or not?"
"Slow down. I was just getting to that. Now here's the shocker…one sample was viable. I tested against all available databases, and that's where we have a problem."
Grissom could feel his patience quickly evaporating. "Just spell it out Greg!"
"Ok, ok. The hit I got was on the Law Enforcement database. Our perp is a cop."
Catherine inhaled sharply and brought her shaking hand to her temple.
"You didn't get a perfect match?" she asked quietly.
"No, all we know is that the killer was once, or still is a member of Vegas law enforcement. Hell, he could be LVPD for all we know."
"Shit!" Grissom spit out bitterly. "This is just perfect."
Catherine glanced worriedly at him, longing to smooth the wrinkles from his brow. Greg was right, this complicated things. Now, in addition to searching for the killer of a friend, they were searching for one of their own.
"Cops killing cops," she thought to herself "how much worse can this get?"