The science just about killed me on this one! Nanotech is hard for the uninitiated. I hope I did it some justice. Anyway, after the long wait, I won't keep you from this latest chapter any longer. A warning, though: it's the longest I think I've ever written for this story. Well then, you know the drill! XOXO

Chapter 10

S.T.A.R. Labs, Treatment Room, 9:10 pm

Caitlin and Digg were too busy prepping their soon-to-be work area to mind Cisco's mounting excitement. He had been exploiting several possible workarounds for Ray's nanotech to work within the parameters Caitlin had set – with No. 1 being that the whole thing does not end up killing Barry and with No. 2 being that they had to take advantage of field dialysis as their delivery mechanism.

The way he figured it, he just had to adapt Caitlin's idea of affixing Ray's nannites to the polymer in the dialysis solution. But with a lot of moving parts that need to work to get everything right, he thought to just go ahead and incorporate Caitlin's whole diagnostic system and adjust it to function with Ray's nanoparticles. Her system was already proven and can be modified into a two-step detection method that uses one antibody as the biosensor that targets the toxin and another antibody as a reporter that would emit a fluorescent signal when the toxin has indeed been acquired. He could then easily conjugate both those antibodies to the nanoparticles and they had their toxin-targeted detection system. That was the easy part.

The part that had him thinking was how exactly to signal the nannites to form a capsule around the captured protein and how to restrict the encapsulation process to an area of Barry's body which they can have ready access to via dialysis. He had been waiting almost impatiently to see just exactly how his workarounds would pan out when his workstation pinged with the results of his latest simulation.

"Boom!" He exclaimed as he went through the read out. "That's how you do it!"

"You got everything to work?" Caitlin asked as she came over to his workbench after wiping down all exposed surfaces and equipment with antiseptic. She knew that he didn't get that excited without something going either extremely well or enormously wrong for him.

"Theoretically, but we'll probably have to go step-by-step, since we basically have a five-part problem here. Part 1 is how to make Ray's nannites recognize the toxin. I figured that we should go ahead and use your diagnostic system for that. We could use an antibody that targets the invariable base of the protein to maintain a 1:1 toxin-to-antibody ratio. Then, we couple the toxin-targeted antibodies with one vial of the nannites, and then inject these biosensor conjugates into Barry's circulation through his IV so that they could essentially search his entire body for their target. Meanwhile, we also conjugate our reporter antibody to another vial of the nanoparticles and affix the hybrid to the polymer in the dialysis solution, just like you said. That way, we can keep track of all the nanoparticles we introduce."

"So, basically we have two halves of the whole. Question is how do we bring those two halves close enough to each other for them to encapsulate the toxin?" The doctor pondered.

Cisco replayed the simulation he was working on as he explained, "That's where Parts 2 and 3 come in. Part 2 is how to direct the nanoparticles to where we want them to be. Ray's nanoparticles are magnetic. We can direct the sensors to where the reporters are and make them close enough to each other by applying an external magnetic field."

"But wouldn't the magnetic field also affect the reporters?" Digg said as he joined them. He had turned on the UV lamp to sterilize the tented area where they would be doing the procedure and was just waiting for enough time for the irradiation to do the job.

Caitlin answered, "In field or peritoneal dialysis, we take advantage of the peritoneal membrane – in this case, the natural physical barrier between the dialysis solution and Barry's blood – and its impermeability to the polymer in the dialysis solution. By affixing our reporters to the polymer, we essentially prevent our reporters from ever escaping into the circulation, even if we're using magnets to direct our sensors towards them."

"And when the sensors, which are small enough to pass through the membrane, cross into reporter territory, then we've basically moved the staging area for the rest of the process away from Barry's bloodstream, and confined it within the peritoneal cavity, which we can, in turn, access via the abdomen," Cisco added.

Digg nodded his head. He appreciated them making every effort to makes things more understandable to him.

Once the question was settled, Cisco picked up his explanation once again, "Part 3 is how to signal the nannites to encapsulate the protein. We know that when our detector binds our sensor and sandwiches the toxin, a fluorescent signal is released. Fortunately for us, that near-infrared signal seems to work well in catalyzing photoreactive nanoparticle self-assembly. So, basically, once the two halves we have meet and form the nanoparticle-toxin core, a kind of nanoflare goes up and the free-standing nanoparticles rush in towards the signal and start building a protective shell around the core.

This is where the third vial comes in. We introduce these non-conjugated nannites as free-standing molecules in the dialysis solution. We localize these particles to the peritoneum the same way we direct the sensors – with magnets."

"Okay so we essentially have a system that can direct and localize everything out of his circulation. Part 4, I guess, addresses how we get those capsules out?" Digg asked Cisco.

At Cisco's nod, Caitlin answered the implied question, "We could do that by flushing the now toxin-contaminated solution out through the dialysis catheter we would be embedding in Barry's abdominal cavity."

"Yes!" Cisco agreed. "Then Part 5 is figuring out how to reuse them. Good thing for us is that the self-assembly process also happens to be light-reversible," he said as his simulation ended with the nanoparticles breaking up and releasing the core after reacting yet again to photostimulation. "Then, all we need is to separate the different nanoparticles from the now toxic solution before we can do everything all over again," he smiled as he finished his presentation. And then his smile turned sad when he came to miss the real genius that had been Ray Palmer. The man had been right when he said that this technology was going to be the wave of the future.

"So, how long until we get this ball rolling?" Digg asked.

"Oh," Cisco said as Digg's question pulled him back from being almost too maudlin. "Just give me a few minutes to whip up everything," he said as he started on yet another assignment. "Caitlin, I'm gonna need your help."

Central City, S.T.A.R. Labs, 9:15 pm

"This doesn't make any sense!" Felicity grumbled as she paced in front of a projection of the virtual evidence wall she and Oliver had built in the past few minutes to plot out and summarize all their key findings in the case. There in the center was part of the malicious code she had newly deconstructed.

"Hmmm?" Oliver queried as he looked up from reading the files Cisco had unearthed from Barry's hard drive.

"The payload – the spyware – it's too sophisticated." She answered as she made her way back to her seat beside him. She had figured out what the other elements of the payload did. She had already uncovered how it had gained access to the CCPD network and how it could initiate outbound network connections. Now, she had found a RAT within the system. RATs, short for Remote Administration Tools, are essentially programs that give a remote operator full access to control a system as if he had physical access to that system. RATs were nothing new to her – she used them regularly – but what bothered her was that the code, which seemed too elegantly written, remained unused.

"I mean, if someone could write code like this, why would he or she risk recognition by getting Barry to infect the network – a poorly defended network at that – when everything could have been more easily done remotely? It doesn't make any sense," she continued. From her perspective, if the shadows are a hacker's best friend, any hacker who's worth their salt – as the author of this code seemed to be – would work overtime to keep it that way.

Oliver pondered the situation. He thought that maybe being a counter-surveillance expert overcame that risk but that didn't fly. In that arena, it was always best to operate as covertly as possible. Felicity was right that it didn't make any sense – unless of course, the perp isn't a hacker, he thought. "What if we assume that whoever this is isn't a hacker but an end-user?" he posited.

"That… that…" she stuttered as she blinked and then she smiled. "I now remember why I keep you around," she teased as she rolled her chair closer to him to kiss his cheek.

Oliver smirked as he felt her lips on his skin.

"Now, I can add another parameter to my search," she said as she moved back to her console. She had deployed a number of her bots to scour all known federal and commercial virus definition databases to look for any similarities in the script, the temporal signature and other digital 'patterns of life' between their samples and this payload. Now, she had to tell her bots to also look for similar software that had been stolen or sold. "Anything new on your end?" she asked as she began to type in her commands.

"Cisco was right about the victims not all having the lip rash, but they did have suspicious skin findings in other, ahem, less exposed parts of their bodies," he answered as he queued up the pictures for Felicity to see for herself.

Felicity tried not to cringe as she scanned through the pictures (one was even captioned 'probably severe latex allergy'). Those victims probably got a little too much of what they'd bargained for, she thought as she shook her head. This just proved that death by kiss was still so obviously on the table and strengthened the possibility that the aggressor was female. A femme fatale, she thought, who must have had a pretty humongous reason to murder those men if she would go as far as debasing herself in order to accomplish the task.

The double beep of the comms alerted them to an incoming call and diverted their attention. Oliver tapped his keyboard twice to answer the call and put it on speaker.

"You're on," he said.

"We're in," Lyla's voice said over the secure line.

"Copy that, Harbinger," he answered as Felicity started to trace their signals and overlay them as pulsing dots on the Gardens' Main Pavilion's blueprints. She may not be able to hack her way in but she had found a way to help by commandeering one of the S.T.A.R. Labs weather drones that was serendipitously in the right place in its flight path to be used as their remote eyes for this little mission. "What's your status?" he asked.

"Heading to the target now. Speedy's on mission. Canary's on the lookout," she answered.

"Here, here," Laurel chimed in.

"And I'm on overwatch," Felicity joined in as she overlaid the weather drone's real-time hyperspectral images on the screen. This way, she could isolate Lyla, Laurel and Thea and alert them to signatures that are moving their way.

"Overwatch has all of you in sight." Oliver said as he officially acknowledged Felicity with her own brand new codename. He saw her smile. "Proceed with caution. Over," he said, as he smiled back at her.

"Copy. Stand-by," Lyla answered.

Starling City, Botanical Gardens, 9:18 pm

Lyla scanned the hallway for the door that leads to the Pavilion's main security room. Felicity had signaled the all clear for her to proceed down the hall.

Laurel was just outside, where the other end of the hallway led to the Pavilion's main exhibition hall, pretending to take a call. The plan was for Lyla to play drunk – and she had doused her unremarkable black chiffon gown with a generous splash of alcohol to play up the effect – and to 'mistake' the security room for the bathroom to draw whoever was in there out. Everything else they were left to do by the seat of their proverbial pants.

"Got the door?" Laurel asked through the comms.

"Still looking. Wait, I've got eyes on it," Lyla answered as she kept up the illusion of her intoxication by wending her way to it. There was no light shining underneath it and it had a keycard lock. Good thing they didn't need a digital lock picker for what she was about to do.

"Overwatch, anything on the inside?" she asked as she laid herself against the door.

"A lot of equipment running hot… And from the looks of it, a single guard," came the answer in her ear.

"Roger that," she said as she acknowledged the last transmission. "Here goes nothing," she warned her team as she started to pound loudly and 'drunkenly' on the door.

It opened to reveal one angry guard. "Lady, this ain't the bathroom," he said as he disgustedly scrunched his nose.

Lyla, who had been leaning on the door, had fallen on him, and slurred, "But… but… the man there said…"

"The bathroom's at the–"

He was interrupted by Lyla pretending to vomit. At the guard's continued hesitation, Lyla let out another exaggerated heave. She needed to force him out of the room, where she could drug him out of camera range.

But instead of bringing her to the bathroom, the guard took her into the room and directed her to the facilities within. Lyla went along with it. She had just been supposed to wedge the door open for Laurel to take over the security room once she had neutralized the guard. But this, she smiled as the guard left her inside the security center's bathroom, this was even better.

xxxxXXXXxxxx

"We're good. Come on in," Lyla said after she had disabled the surveillance system and opened the door for her accomplice. She had already accessed the archive when Laurel finally came in.

"You got in?" Laurel asked as she entered the room and took in the now dozing guard.

"Yes," Lyla answered as she brought up the video feed menu and called up all stored footage from two weeks ago. She had been sorely tempted to copy the entire day's files to the hard drive Laurel had unstrapped from her thigh but how long the guard stayed down was unpredictable. She wouldn't risk discovery for that so to Oliver, she asked, "Which area do we focus on?"

"The reception area after the talk in the auditorium," he replied, "I remember seeing a camera by the elevator so there must've been at least one angle covering our friends."

"And also the auditorium entrances at least an hour before and after the talk," Felicity added. "The more angles you get, the more information we can give to the gait recognition software to analyze."

"Okay," Lyla said as she began to queue up the files from all possible cameras that would have most likely captured their friends, and therefore, their perp.

Laurel in the meantime started scanning the sequences that Lyla had called up on the bigger screen. "Okay, I see them," she said as she spotted Oliver, Felicity, and their Central City friends in the footage. She repeated the marking process as Lyla queued up more footage.

Lyla then began to isolate the footage coming from the camera angles Laurel had marked. All in all, they had about 6-10 angles to choose from at any one time.

A groan erupted from the guard.

Lyla quickly began to copy the files they needed as Laurel scrambled to tidy up the room and make sure they left zero evidence of the theft, including the syringe containing the drug Lyla had used to knock the guard out. He could be waking up soon.

"How long to copy?" Laurel asked as she came back to the console.

"Twenty seconds," Lyla whispered as she oversaw the transfer.

At another groan from their unwilling victim, Lyla moved out of the way as Laurel wheeled the guard back to his position in front of the screen.

"Ten," Lyla counted down as she began wiping down the console and the guard's chair to clean up their prints.

Laurel already had her hand on the drive, ready to rip it out and make a run for it.

"Hallway's clear for exit," Felicity said over the comms. "Run when you must."

The blue light on the drive stopped blinking as the guard began to stir. Laurel ripped it out that instant, stashed it in her clutch and made for the door. Lyla gave Laurel a few more seconds to clear the hallway before she restored the cameras and made her way back to the security room's bathroom.

xxxxXXXXxxxx

"Are we good?" Thea asked to no one in particular via the comms once she got away from the crowd. Even if she had been hobnobbing with Starling City's elite, her ear had been privy to everything that was going down behind the scenes. When no answer was forthcoming, she surreptitiously allowed her eyes to roam the room. She caught Laurel huff as she entered the Pavilion. "Package is secure," Thea saw the Canary mouth as she heard it through her earpiece.

"Harbinger?" Thea asked.

"Overwatch, I don't have eyes on Harbinger," Laurel reported at Thea's query.

"Her comm's still active," Felicity said. "She's still in the room."

They all held their collective breaths as they waited… and waited… and waited…

Until static noise buzzed into their ears and was followed by their teammate's crackled voice, "Harbinger here. I'm clear. I'm okay."

Central City, S.T.A.R. Labs, 9:25 pm

Felicity and Oliver both exhaled their relief as Lyla's voice came through.

"I have a visual," Thea confirmed.

"Good to hear that, Harbinger!" Oliver said as he sat back down. All the worry had him standing tensely the past few minutes. "Now, come home. Over," he commanded.

"Copy that!" Thea and Laurel exclaimed at the same time.

"Wilco, out," Lyla said as she ended the transmission.

Oliver rubbed his thumbs over his eyes as he leaned back on his chair.

"They're fine," Felicity said as she rubbed his bicep to soothe him.

Oliver exhaled and nodded. "I know," he said as he looked at her. "I know."

Felicity patted his arm twice as she smiled at him before she went back to work.

Central City Police Department, 9:30 pm

Joe had made a detour back to his office, where he was now unearthing his files on this case. When Val mentioned Twilight Mist, he had begun to get a nagging feeling that there was a connection with his victims that he was missing. It got stronger when he left Vice, so he had postponed his trip to Barry's office to instead head into his own, to scour his files to confirm his inkling.

True enough, his files bore out his gut feeling. There buried in the last pages of the first file was information that named one of the victims as a person-of-interest in relation to a case alleging the sale and illegal distribution of prescription and illegal drugs including Twilight Mist. The victim was thought to be one of the straw men who brokers deals for gangs and the like, with legitimate pharmaceutical companies to get a line on pure product.

He then reached for another file on his desk. It was the alderman's file. He reviewed the case and the newspaper clippings he had just skimmed before and found out an important fact he seemingly ignored – it was the alderman who had pushed for the conversion of the docks into a Freeport zone. The last file was thinner than both. The third victim was a strip club owner with no priors but who's allegedly involved with human trafficking. No new information or epiphanies jumped out at him, but he knew right then that he was onto something.

That's 2 out of 3 with a known connection to drugs and the docks, he thought, as he stood and started to make his way to Barry's lab. The third case could also very well be connected to either but he had yet to find more information to substantiate that. But between what Detective Perez revealed and this, 2/3 was enough to put his other team on this, he absently ruminated.

It didn't take long for his feet to find its way to his destination. Joe had been so lost in thought about the ramifications of his new findings that he had briefly forgotten why he was where he found himself.

Barry's phone, his brain supplied.

Ah, he thought as he made his way to the switch to open the lights.

The coffee stain that marred the floor was still a blatant reminder of all that he could've lost. He sighed as he circled the room.

Just then, his Cisco phone rang. It was Felicity.

"Hello," he answered.

"Hi, Detective. I was hoping to follow-up with you about Barry's phone?"

"I'm actually on it. Hold on a sec," he said as he crouched down and surveyed the floor. Barry's phone was last seen when his son had taken a call earlier that morning. It didn't appear in any of the evidence logs or evidence boxes, or in what he could remember of Barry's personal effects upon discharge from the hospital. The footage also placed Barry by his desk when he collapsed. So, maybe it made sense if he started there.

He looked beneath Barry's desk. Nothing.

He had then looked under his equipment and work bench and even under his cabinets. Nada.

So he stood up and took a few steps back until he hit what he called Barry's obsession wall. The board was jostled and prompted him to look back as a tether seemed to have snapped and a whole layer of the board rolled up.

"Detective?" Felicity asked as she heard the snap. "Detective, what's wrong?" she prompted yet again as Joe failed to give an answer.

Joe couldn't believe his eyes. "I'll be with you shortly," he said as he clicked off the call and used his phone to snap a photo. This case just never wants to end! He thought while exasperatedly scratching his head as he headed out of the room.

Somewhere in Central City, 9:40pm

A lone figure sat in the dark somewhere in Central City, watching keenly from a screen, as the detective rushed out of the frame. Without the man blocking the view, the shadow in the darkness saw just exactly what urged him to move and so swiftly.

Shit. The specter shook its head.

It was time to make a decision.

How'd you like it?

Anyway, please accept my heartfelt thanks for your continued support! Don't forget to let me know what you think. Reviews/comments/follows/faves are always, always appreciated! Kisses!