Marlena left the lab in a hurry and escaped to the ladies room where she quickly dug into her pocket and withdrew a lighter and the last cigarette of her pack. She'd been smoking secretly for at least twelve years—not even her parents knew. And she was very good at keeping it a secret.

Quietly, she hopped onto the radiator and pulled open the window. The night was chilly and the desert brought in a zephyr. She shivered a little.

I'm going to quit smoking tomorrow, she told herself, something she'd say every time she lit up. It was her inside joke with herself.

It wasn't until she was just about finished with the cigarette that she noticed the tox screening was still in her hand. She groaned and read it again. Strychnine. She didn't recall seeing any strychnine at all in Grissom's cabinets. So the strychnine came from an outside source.

But where?

The maid could have brought it in with her.

But how?

Marlena felt very tired. She finished her cigarette, doused it in the sink and chucked the stub out of the window, wondering if she'd made the wrong career choice.

She exited the bathroom and sort of flapped the hem of her T-shirt, trying to get the smell of cigarette smoke out. Just then, Catherine Willows stalked down the hallway. If looks could kill, Marlena would be dead already.

"Marlena, no smoking in the bathrooms please," she said as she passed, and kept walking.

Inconspicuously, Marlena put her nose to the hem and sniffed. It sort of smelled like smoke, but not overwhelmingly. She spent the rest of the night trying to figure out how Catherine had managed to smell that.

Going into her locker, she changed T-shirts just in case anyone else got a conniption from the slightest scent of tobacco and/or smoke. Next, she sought out Breeze who Marlena had put to work matching the fingerprints found in Grissom's apartment.

"Where's Sasha?" she asked her.

"I don't know. Why do I smell smoke?" Breeze asked, sniffling.

"I've been smokin' in the girl's room. But never again. Is it in my hair?"

"Uh-huh." Breeze yawned and rubbed her eyes. Just as they focused, the computer came up with a match. "Whoa." She stared at the blinking screen.

"What?"

"You're gonna wanna see this," Breeze shook her head.

Marlena came up behind her to peer over her shoulder at the computer screen. "What?"

"Well, these fingerprints from the table, chair, a wine glass and every bottle of the meds were from Grissom," Breeze said, showing Marlena the prints. "These are from the door, a vase, two bottles of the medications, the table and the chair and some of the drinking glasses belonging to Solange Tanguy." Another example was shown. "Here's where it gets interesting. These were on the door, the table, the chair, a wine glass and four bottles of Grissom's herbals. They belong to Heather Jeanne Paruvski, also known as Lady Heather."

"Lady Heather? That sounds familiar."

"It should. She runs Lady Heather's Domain, a website and a…well, some would say whorehouse, in Las Vegas. Lady Heather was involved in two CSI cases in two years, both dealing with deaths of her employees."

"So it puts her at the scene of the crime."

"Well, yes. I think we might have to have a talk to her."

Marlena wrapped a piece of her hair around her index finger and tugged on it a little. "What else is there that I should know?"

"This," Breeze pulled up the last print. "This was on a few cabinets, a chair and the door knob and also every bottle of Grissom's herbals. Check it out." Breeze pulled up the print.

What Marlena saw made her blood run cold. She looked in surprise at the fingerprints Breeze had matched. "That's not…are you sure?"

"Yup. AVIS never lies, does it?"

"Well," Marlena couldn't help but shake her head as well. "Looks like we have a suspect in our own midst."

"What do you wanna do about it?"

"I'm not sure yet," Marlena sighed. She began to pace and bite her thumbnail. "What would Sara Sidle be doing at Grissom's place?"

"Were they friends?"

"Coworkers first, friends second. That's what Sara tells me all the time."

"I also sent the hairs you found to Sasha for him to analyze. He should be doing that now but I haven't seen him in a while."

"If that's Sara's hair, I'll seriously loose it. I'll go crazy."

"I got a good look at them under a light before I sent them to Sasha. Some are dark red. Some are black. Sara, if I'm not mistaken, is a brunette."

"But we can't get DNA from hair unless it's pulled from the roots. We might not have given Sasha enough information."

"Get a sample of Sara's hair and compare-and-contrast."

"Yeah, like it's that easy. I'll have to get samples from Heather and Solange, too."

Breeze raised her pierced eyebrow again, "Sounds like you're finally getting a hang of this job."

"Sash?" Marlena said when she found him at a table in the break room looking over some paperwork. "I need you to come with me to Solange Tanguy's house."

Sasha looked up, "You mean, Mrs. Clean?"

"Yeah, whatever thrills you," Marlena rolled her eyes and sat down across from him. "I need your fiber analyzing talents."

"I am at your disposal," Sasha smirked.

"Sure," another roll of the eyes made Sasha back off. "Sash, I think something on Solange might have brought the strychnine into Grissom's house."

"He lick her clothes or something?"

"She's the cleaning lady. She uses and has access to all types of chemicals. Please, Sasha…"

"Marlena, they found the strychnine in his blood. It was a tox screen!"

"It couldn't hurt to look, Sasha. She found the body. She could have something connected with the murder. Footprints, fingerprints put her at the scene of the crime."

"Did you find her footprints or fingerprints?"

"Yes and I think hair, too."

Sasha groaned and stood up, "I'll go check out where she lives."

Marlena knocked on the door of Solange Tanguy's current residence, apartment 62B of the Egyptian Gardens Complex, the aqua paint of the entrance peeling badly. As they waited for an answer, Sasha looked around, up and down the corridor, listening to the sounds coming through the paper-thin walls. The hall was like an oven. Today was not a good day to be wearing long pants, like both Marlena and Sasha were.

Finally, a thin woman wearing a flowing, silky yellow muumuu answered the door, but it was not Solange. But like Solange, her skin was onyx and her eyes and dread locked hair matched. She was smoking a long, thin cigarette that gave off the faint scent of vanilla.

"Can I help you?" she asked in English with a thick Trinidadian accent that reminded Marlena of jumpy ands festive music. Her tone, however, was grave.

Sasha flashed his ID, "Sasha Zarek and Marlena Reagan from the Las Vegas Criminalistics Bureau. We have a warrant to search your residence for evidence in a homicide."

Marlena held up the warrant and her ID at the same time, a little awkwardly.

"Dis about Solange?" the woman leaned one arm on her doorway. "Dis about de man who died?"

"Yes."

"Come in, den," the woman opened her door a bit wider and beckoned them to enter.