It had been fifteen years since Jane Rizzoli had last seen Kate Beckett, back at the NYPD training facilities where she'd had a twenty week placement during her rookie training. They hadn't spoken since, but Jane had kept an eye on Kate's progress through to being a detective in the homicide department in New York. She'd read about the big cases Kate's team had solved, the death of Captain Montgomery, and the shooting ("Oh my god Kate what have you gotten yourself into"), but her own pride and stubbornness had kept her from making direct contact. Even fifteen years on, thinking about how things had ended still hurt.

So when Detective Kate Beckett and her team walked into Boston Homicide late one afternoon, Jane's mouth fell open and she could only stare dumbly at the woman who had once meant more to her than anyone else. She could vaguely hear Cavanaugh declaring that a team of detectives from NYPD were there to assist with their latest case, a serial killer who had killed at least six people in New York last year before reappearing in Boston and taking the lives of two people so far. While the people who were being killed seemed to be chosen randomly, with no connections at all, they had all been left the same way – locked in a room or storage container somewhere with a stab wound to the abdomen, left to bleed out in the darkness. An anonymous call made from an untraceable number would give police the exact location, but there were never any clues as to who may be involved or how the victim was chosen. It had been a frustrating week, and Jane wanted nothing more than to catch the creep doing this.

Although right this very moment, she wanted nothing more than to sink into her chair and disappear before Kate Beckett, the women who broke her heart, turned around.

Cavanaugh introduced the visiting team. "Everyone listen up, this is Detective Kate Beckett and her team, Detective Esposito, Detective Ryan and Det-, uh, Mr Castle. They've been following the New York cases and they're the best from NYPD, so please make them welcome here. They will be working closely with Detectives Korsak, Frost and Rizzoli until this guy is in a jail cell."

As he introduced them, Cavanaugh pointed his detectives out to the visitors. Jane forced herself to make eye contact as Kate's eyes fell on her, registering the flash of shock there, but quickly dropped her gaze. Frost raised his eyebrows at this, and once the NYPD detectives had moved away to be shown their temporary desks on the other side of the room, he leaned over to his friend. "What was that about Jane, you guys know each other?"

Jane sighed and buried her head in her hands. "Sort of," she muttered, sounding miserable. "We did part of our rookie training together in New York." When Jane didn't elaborate, Frost decided not to push his luck and left Jane to sulk at her desk.

An hour later, Kate was still trying to make sense of the emotions she felt coursing through her body when she saw Jane. She had known that Jane was with the BPD, but hadn't been aware that she was a detective in the homicide division, so seeing her had been a surprise. Jane was still incredibly beautiful, but she looked harder, with sadness in her eyes. Kate wondered for a guilty moment if that was partially her fault.

While these thoughts were running through Kate's head, Jane was subtly observing her and the rest of the NYPD team from across the room. The two detectives were talking animatedly and gesturing at a file that the taller one was holding, while the writer – Mr Castle – was joining in, and also casting the occasional confused glance at Kate, who was staring at her own file, deep in thought; although Jane noticed that her eyes didn't seem to be moving across the page. She wondered if Kate knew that the writer was in love with her, it seemed obvious every time gazed at her. A wave of jealousy rolled over Jane, until she mentally shook herself. Kate broke up with her fifteen years ago, and she was still jealous over other people wanting her? Get a hold of yourself Jane.

She became suddenly aware that someone was standing right beside her desk, and her eyes widened as she realised it was Beckett, who was fidgeting nervously. "Hey, can we… can we talk for a second? Before we get stuck into this case?" Kate asked quietly. At a loss for words, Jane simply nodded and stood, pointing the other woman towards the empty breakroom. She closed the door behind them and turned to face her ex, heart pounding painfully.

"Jane."

"Kate."

There was silence as their eyes finally met, staring for a split second before they both spoke.

"It's good to see you-"

"I'm sorry I haven't kept in touch-"

Both stopping at the interruption, their eyes met again, and suddenly both Kate and Jane were laughing. Kate quickly moved across the breakroom and embraced her former friend, holding her for a second long than she would anyone else before releasing her. "You know," Kate said, smiling, "I almost had a heart attack when I saw you sitting there."

Jane returned the grin. "You almost had a heart attack? I think my blood pressure went through the roof! It was worse than that time at training when Taylor made us do eight laps of the running track for…" Jane trailed off suddenly, feeling her face flush as she remembered exactly what Taylor, their sixty-year-old police academy trainer, had caught them doing. It was Kate's turn to raise an eyebrow. "After he caught us making out in the gym, if I remember correctly." She said, laughing. Glad that there wasn't too much awkwardness between them, Jane laughed too. "Yeah, poor guy. Seemed like a drastic punishment though. I'm glad you're here Beckett, sounds like you guys are the best in New York. We could definitely use your help on this case."