It was like the arrival of a monarchy: the front doors swung open, bringing a wave of stifling Las Vegas heat into the lab as they swept through the reception area. A quick flash of their badges and they were promptly waved into the maze of corridors without so much as a raised eyebrow.

The well-dressed entourage came to a halt outside the break room, and the leader of the pack stepped out of line.

"Mr Ecklie?" A stern voice enquired, drawing to it three pairs of eyes.

"Yes." Conrad cleared his throat, rising from his seat with his hand already extended in greeting. "Internal Affairs Bureau?"

"Agent Jerry Connolly." The suited man asserted, flicking his gaze to the other two men lurking in the room. "Mr Jordan and Mr Grissom, I presume?"

"Doctor Grissom." Gil corrected testily as all three supervisors begrudgingly shook hands with the agents.

"Noted." Connolly nodded bluntly. "I understand that you've all been briefed." They murmured their agreement. "And your teams – they're all aware of the situation too?"

"Yes, they are." Ecklie jumped in hurriedly. "And I can assure you, they are all just as eager to solve this as you are. I can promise you will have their full cooperation."

"Excellent." Connolly gestured to the two men behind him. "These are Agents Mac Keefer and Jim Frazier. Keefer will be working with the Day Shift team, Frazier with Swing," he nodded imperceptibly at Bobby Jordan. "And since it was a night shift case, I'll be working with the Graveyard shift."

Grissom visibly twitched at this news. He had expected as much, but he was still not thrilled to have it confirmed. Everything about this man's demeanour, from his perfectly pressed suit to his flawlessly combed black hair, suggested he was a stickler for the details.

"Alright," the supervisor resigned himself to the fact, dropping his shoulders miserably. "We'll do a debrief at the start of shift to catch you up to speed."

"I've read the report." Connolly countered, almost insulted at the insinuation that he was in some way out of touch with the investigation.

"Yeah," Grissom licked his lips, unable to resist the opportunity to get one up on the man. "But we work fast ... I wouldn't want you to fall behind."

X x x

"Alright," Catherine slapped her hands onto the table. "Let's rewind. What do we know?"

The team shifted, all too aware that they were being observed. It was never a party when IAB rocked up, but it was even worse when it was your own team being dissected like pinned frogs.

Recognising the pleading expression in Cath's eyes at the deathly silence that followed her question, Sara decided to bite the bullet and be the first to speak up.

"Okay, the husband, wife and teenage son were all killed in their home; both adults were stabbed, the son was shot." She paused, flicking her eyes briefly to the agent scrutinising her from the corner of the room. "The six-year-old daughter was spared."

"This lighter was found in the son's room," Nick took over, tossing the evidence bag into the middle of the table. "Family members and friends confirmed that no-one in the house smoked."

"That's where things got dodgy." Warrick coughed, determining to avoid the piercing gaze of the IAB officer; unlike his more obstinate colleagues. "When we tried to test for DNA and prints we found the samples degraded, due to LGM contamination. But, the contamination was on the side that was against the carpet which means the lighter was placed there after we started processing."

"And we know that the only people on site at the time were CSIs and cops." Catherine surmised with a deep breath.

"Alright." The agent spoke at last from his shadowy hole between the door and the whiteboard. "Who was at the scene at the time?"

"All of us." Nick shrugged. "It was a big scene."

Connolly double-checked the register, having already known the answer, before glancing up to meet Catherine's gaze.

"You weren't, Ms Willows." He pointed out. "According to this, you didn't arrive until two hours after the evidence was collected."

"I couldn't find a babysitter for my daughter." She answered swiftly. His narrowed eyes suggested he was not convinced, taking a long few seconds to decipher the response. She could have sworn that he was trying to read her very thoughts, his stare was so intense.

"Okay." He nodded sceptically at last. "Who was it that collected the lighter?"

"I did." Warrick asserted, straightening up and squaring his shoulders in an obvious attempt to appear as large as possible. "I found it under the kid's bed skirt."

"Was anyone else around when you found it?"

"Hey," Warrick snapped defensively. "I don't like where you're going with this..."

"Warrick." Grissom, until now merely an observer in this little rehash of the scene, cut in quickly before the hot-headed CSI could lose his rag. "No one's accusing anyone on this team of evidence tampering – are they, Mr Connolly?" His tone left no room for argument; and the officer began to squirm under the intense gaze of the grave-yard shift in its entirety.

"No," he cleared his throat at last. "Of course not."

In the awkward silence that followed, Catherine pursed her lips.

"Alright Agent Connolly, why don't you come with me. I can bring you up to speed on the evidence we have so far in the case."

The rest of the team watched them slope out, a mix of gratitude at Cath taking the heat away from them from a while; and pity for her having to deal with an Internal Affairs shadow for the remainder of the shift.

X x x

"So," Connolly hummed, dragging his hand lightly across the bags of evidence littering the table. "How old is your kid?"

"Sixteen." Cath answered absently, too focused on her task at hand to notice the officer's eyebrows shoot up in surprise.

"Oh." He blinked. "I assumed when you said you needed a babysitter that she was ... a child."

This time Catherine stopped what she was doing to address him with her full attention, her eyes flashing with indignant anger.

"She is a child." The strawberry-blonde snapped. The agent almost recoiled in surprise at her sudden change in character, holding up his hands in defence.

"Okay." He pulled a face, reluctantly conceding to her point. "But, come on, most sixteen year olds can survive on their own for a couple of hours during the day; don't you think?"

"No, I don't." She retorted sullenly. "And I don't think it's any of your business how I raise my child."

"Ms Willows, with all due respect; a teenager is not a child."

"Oh please," she snorted. "What the hell would you know about raising kids?"

"You're pretty opinionated, aren't you Ms Willows?" He challenged. He wasn't sure whether her question was rhetorical or if she was actually expecting an answer, but he choose to sidestep it all the same. You do not allow your personal and professional lives to crossover - it was a rule he had lived by resolutely for many years and he was not about to break it now

She emitted a bitter laugh, shaking her long hair out.

"What the hell does that have to do with anything?" She barked, realising all too late that she was walking head-first into a well-known federal trap.

If you can't discredit the evidence, discredit the professionals; or let them do it themselves.

Thankfully, before she could cram her foot any further down her own throat, they were interrupted by a rather off-colour Archie.

"Hey, sorry to interrupt." He held up his hands, looking anything but sorry to be breaking up the heated fight.

"What is it Archie?" Catherine asked, clawing a stressed hand through her locks.

"I've been checking the Wilson's computer – you ... you guys are going to want to see this."

X x x

"Okay, I was checking the husband's laptop – check this out." He tapped a few keys, bringing up a series of hidden folders.

"Oh no." Catherine groaned, her face visibly paling as she instantly recognised what they were looking at. "How bad is it?"

"I'm only on the first folder." Archie confirmed grimly.

"Hey, I got your page." Grissom rushed in; too late, as ever. "What's the news?"

"Child pornography on the dad's computer." Catherine explained bluntly, fighting back the bile rising in her stomach at those all too familiar words.

The look on the supervisor's face pretty much summed up the general opinion on the matter, as his face contorted into a sickened scowl.

"Oh." He swallowed. "Well, at least that may give us a motive."

X x x

"Hey Arch." Nick greeted, exhaustion evident in his heavy voice and slow, weary movements. "How's it going in here?"

"I think I'm going blind." The tech shook his head, his eyes wide with the effects of too much caffeine. "There are thousands of downloaded images on here." He skipped through them, barely even registering the shocking nature anymore. "They range from young girls to teenagers; though there's nothing so far to suggest he's distributing as well as downloading."

"Hey, wait stop!" Nick barked, dropping a hand roughly onto his shoulder. "Go back!"

Archie did as requested, flicking back a couple of images until Nick's fingernails digging into his shoulder blade indicated he had hit the right one.

"Oh man," the Texan groaned, his dark eyes falling shut.

Archie scrutinised the photo, trying to place the face.

"Is that...?"

"Yeah," Nick licked his dry lips. "And this case just got a whole lot worse."