This is a sequel fic to my first Criminal Intent story including my OC Abby, Crusader. That story details how Bobby and Abby met and all their initial details. So give that a read if you want some back story on them, if not then just read on here and enjoy :)

Chapter 1: Colours of Numbers

Goren didn't believe in coincidence, or leaving things to chance, he liked statistics and facts. So, statistically, if he walked the street Abby lived on as a shortcut to get a taxi to the courthouse, it was to be expected that he might run into Abby one day. That was, of course, if she hadn't moved back to Australia. At least, that's where Bobby thought she was, but on the warm day that he took that shortcut, he heard her voice. Her distinctive voice coming from the small park beside her apartment building.

"Theo, stop staring up at the sun!" Abby was calling to a little boy whose head was tilted straight up. Theo giggled when Abby called to him, and went back to running up and down the slide.

"Abby?" Bobby stood by the gate, squinting in the sunlight to get a better look at her. It was Abby, alright. He never forgot a face.

Abby turned, revealing a small baby in her lap, and when she saw who it was who called her, she looked pleasantly surprised. "Detective Bobby!" She beamed. "What are you doing out here?"

"I have to be in court," Bobby replied with a grin, realizing he was quite happy to see her and wishing he wasn't running late so he could stay and talk. He'd forgotten how he enjoyed talking to her, how he enjoyed her frank honesty. "What about you?" He eyed the baby sucking her thumb on Abby's lap. "Nannying?"

"No," Abby rose to her feet and adjusted the infant in her arms. "Just babysitting, these are my neighbours kids, she's got a bad flu."

Bobby's phone buzzed in his pocket. He knew it was Carver before he opened it because the lawyer had been messaging him nonstop all morning reminding him of the questions he was going to ask him on the stand. Bobby already knew them backwards, it was just the end of a long case that Carver was anxious to finish. "I, ah, I have to run," Bobby said, his mind flush with questions he wanted to ask Abby. "But will you meet me for a cup of coffee?"

Abby seemed taken aback, but tried to be nonchalant. "Sure," she pointed across the street to her local coffee shop. "How about there? Tomorrow for lunch?"

"Great," Goren said, his phone ringing again. "I gotta go, see you tomorrow." And he went off to court, his mood elevated a couple of levels about his prospects for the next day.

Over coffee the following lunch, Bobby was able to pepper Abby with the questions he'd been pondering since his run in with her. "You're still here, I thought you were headed back to Australia?"

"I was," Abby added sugar to her coffee. "I was organizing to go back to university in Melbourne and found out I could transfer my degree to NYU and get credit for the work I've done. In a year, I'll have my computer science degree here."

"So you're back to computer science?" Bobby nodded with approval, Abby had a degree in computer science back in Australia but had been offered a position as a nanny for a wealthy New York couple with a young son; too good an opportunity to pass up.

"Yeah, actually after everything that happened with the Walkers, I've been looking into computer forensics."

Bobby raised his eyebrows. "Fighting online crime?"

"No," Abby smirked. "More like being paid to hack into people's computers and decoding loads of random nonsense. Fun."

"Do you keep in touch with John Walker?"

"Yes and no," Abby sipped her coffee. "He sends me emails on Matty, he's three and a half now it's crazy," she smiled, clearly still bonded with the young boy she'd taken care of for so long. "But John's not working so much anymore, and he says he doesn't have any staff helping him. So that's good for Matty. Leila's never going to see the light of day again," she shrugged. "So he deserves some consistency."

Bobby nodded, he'd been in the courtroom when Leila Walker had been sentenced for the murders of her maid and butler. Since Abby's near-death by poisoning couldn't be attributed to Leila (because Nicole Wallace had decided to inject herself into Bobby's life again making him think it was her who had done the poisoning), Abby wasn't required to appear in court.

"Your brother still here?" Bobby asked. He'd only met Ben Mackenzie once, but he seemed to be a nice guy and he and Abby were close.

"Yeah he is. In fact, he and Kayla are having another baby." Abby said excitedly. "Their third. And I missed the births of the first two, so it'll be nice to be around to help out. It's probably the main reason I chose to stay in the city..."

She spoke about her family with obvious compassion, it was a trait about her Bobby had admired from the moment he had met her almost a year before. She had a big heart, and a warm smile. She'd had both when he'd met her Her hair was honey-blonde but still wavy and dusting her shoulders as it had been before. Everything about her was the same as he remembered, but without the cloud of a homicide looming over her. Bobby was noticing her in a different way. And not just through a detective's eyes.

"You know, you'll probably think that I'm flirting with you, but you have very distinctive eyes." He said honestly. He saw a lot of a someone's personality in the way they held their eyes. "It's your smile, it's in your eyes."

She seemed to bite her lip to keep from smiling wider. "Well," she blushed and tried to cover it with a crooked smirk. "You're cute, too." She made a face like she was saying it just to tease him. But, as well as seeing her personality through her eyes, Bobby also noticed the expression of her reaction was not only genuine, but mutual.

Abby stepped out on the level of the major case squad feeling that same rush of anxiety at being in this building again. Her first time there she'd been a suspect, and then collapsed and almost died. It wasn't her favourite place in the world, but any opportunity to hack computers for money was good by her.

When Bobby had called her the following Tuesday night after their coffee, the last thing she expected him to ask her was for her help. Her computer help. Bobby explained that he and his partner, Alex Eames, were working on a case and their usual computer guy had been admitted to hospital for emergency surgery to remove his appendix.

So, on short notice at six o'clock in the evening with no pressing engagements other than a new episode of Survivor, Abby took a cab to the major case building. Goren met Abby at the elevator and handed her a plastic ID tag.

"Temporary consultant," Abby said reading the label as she slipped it into the pocket of her jeans. "Can I keep this?"

"We'll see," Goren directed her towards the interview room where Eames and Captain Deakins were mulling over a pinboard covered in printouts.

The squad room was as empty as Abby had ever seen it, but she'd only been there during the day when detectives were rushing around. Now, only a few officers dotted the floor, working quietly at their desks. Most of the lights were off shrouding the room in shadows. It definitely lacked the imposing quality it had had on Abby in her previous visits, now it kind of reminded her of a high school after hours.

"Ms Mackenzie?" Deakins offered his hand to Abby as she came into the interview room. "Good to see you again, thanks for coming on such short notice."

"Oh, it's no trouble." She assured the handsome Chief of Detectives, smiling a hello to Detective Eames. "And call me Abby..." her eyes flicked to the pinboard as Deakins retreated to his office to leave them to work. "This is a mess, why are they backwards?"

Goren raised his eyebrows at her. "Backwards?"

"Yeah," Abby approached the board and started to rearrange the printouts. "See this?" She tapped the random mess of numerals in the corner of each piece of paper. "They're gibberish-y page numbers. Letters written in their numeric form." She starting pinning them in proper order. "One is 15-14-5, two is 20-23-15."

"So then this one is three," Goren spoke up pointing to the printout on the bottom left corner. "20-8-18-5-5."

Abby nodded and let him pin it in place. "It's not the hardest code to solve if you know what you're looking for." Truth was, it was often overlooked by people searching way too hard to solve what they perceived to be an intricate, unreadable code, rather than recognizing it was a simple transference of letters into numbers. It didn't surprise her that Bobby, who was easily the most intelligent man she'd ever met, hadn't caught it. Though she did suspect he would have soon enough.

"It's from a teenage boys' computer," Eames told her. "Is this something he would be able to implement?"

"Yeah," Abby nodded. "There are a bunch of programs on the internet that'll jumble up numbers for you that kids turn into a code so their birthday turns into a weird word like TESGA, or something, and then they use that as a password."

"And here I was trying to think of his first pet's name," Eames cell phone rang, so she left the room to take the call.

"You learn this at NYU?" Bobby asked Abby as she continued to inspect the printouts.

"Not exactly," Abby shook her head. "About a month ago, I went to a seminar that dealt with social media and genetic coding kinda like this. Three hours," she rolled her eyes. "But I guess it stuck."

"It's impressive."

"Not really." Abby shrugged. "It's common computer science knowledge. Or so I'm finding out. It was what made me wanna go back to university. Everything I'd learned was updated; there were faster ways to do everything and I wanted to know how. There are seminars all over the city that seem to delight in telling us everything we learned the month before is now obsolete..." she trailed off as she noticed a number pattern repeating on the printouts.

"What?" Bobby asked, seeing her attention sharpen.

"This number?" Abby circled 0b100101 which appeared at least once on each page. "It's a prefix that indicates programming a language. So, all of this?" she gestured to the wall of printouts. "Is probably not in English. So if you do translate it into English, you'll get a bunch of letters that make no sense."

"Any idea what language?"

"No, but you're the detective," she pointed out, smirking. "So detect what language it is."

He smiled at her, holding his eyes in line with her own for an extended moment. "Tesga," he said. "Your birthday... May 20, 1971?"

Abby nodded, again unsurprised he had figured it out. "Yeah, the Australian way. The 20th of the fifth, the day before the month, because for some weird reason you people decided to put the month before the day."

"French," Eames announced as she came back into the room. "This kid and the victim both took a French tutoring class." Eames pointed to the printouts. "If you know the language, you can decipher that?"

"With the right computer and programme," Abby said. "Your tech people could do it."

Goren shared a knowing look with his partner, who nodded, and then turned back to Abby. "Do you need a job?"

xxx