This next chapter moves the story three years ahead, to the end of season 4, when Hailey joins Intelligence in episode "Fagin".

The following chapters will be linked to the actual episodes. I won't re-tell all parts of the cases, only summarize them (as you will probably know all the episodes in detail anyway), and go into detail where it is important for this story.

I hope you like where this is going. And once again, thank you so much for the great reviews

Part 2

Chapter 5

The day started with a weird conversation between Jay and Erin over breakfast. He tried to tell his ex-girlfriend a story about this couple that lived in two separate houses and made the relationship work. Erin didn't think it was funny or even interesting, instead she made him feel bad with just a few words. And she was an expert in that field. If that was how their work partnership would work after their break-up, he was up for rough times. Thank God this conversation was cut short, when they were called to a crime scene. Relieved Jay stood up, and they headed outside, towards the Credit Union a few blocks away.

The Credit Union had been robbed, and several people had been shot. Jay and Erin secured the scene, called the ambulance, took care of the victims, and soon enough Sergeant Voight joined his detectives. They explained what had happened, when suddenly someone in the background gave orders to the officer working there.

Jay froze. Could that be? He managed to turn around slowly, in sync with the others, and keep his emotions to himself, while the person, to whom this voice belonged, approached.

Only Jay noticed that Hailey stopped for an instance, noticing Jay's presence, before she started talking to Voight.

"Detective Upton, Robbery-Homicide," Hailey introduced herself.

"Hank Voight, Intelligence," Sergeant Voight answered, a suspicious look on his face.

"Well, I appreciate the help, Sergeant," Hailey continued. "But as of now this is my scene."

Jay noticed that Erin looked quite surprised at Hailey's demeanor.

"My team recovered evidence and saved a woman's life," Voight replied. "We're running point."

"Make sure those shell casings are photo'd, bagged and tagged," Hailey said to the officer, then turned back to Voight and his team. "I've been after this crew for the last three weeks."

"Then why did my team respond first?" Voight asked Hailey, briefly glancing at Jay and Erin. Jay frowned slightly and stared at his former girlfriend. So Hailey was a detective now. And a very confident one, too. Good for her.

He tried to stay out of it, as he didn't know yet how to play this. He didn't want to give it away to Voight and Erin that he knew Hailey. He preferred to wait with that revelation until it was clear how this situation would turn out.

"I'm from Robbery-Homicide," Hailey said coolly. "There's been a robbery and a homicide here. So I'd appreciate it if you vacated my crime scene."

Raised eyebrows on Voight's and Erin's side, a barely hidden smirk from Jay. Hailey had definitely changed, and Jay liked that change.

Jay and Hailey exchanged a brief look, before Jay left the scene with his colleagues.

Three years earlier

Jay and Hailey were in love, madly in love. They spent as much time together as possible, which to be honest wasn't nearly as much time as they wanted. They couldn't keep their hands off each other, but that was by far not all that mattered. Jay appreciated Hailey's support, he could talk to her about his cases, about his doubts about working with Voight, and about all the tiny little things that happened at work. She understood. Hailey loved it that Jay never looked down on her for being a patrol officer only, or for being a female cop, that he always valued her opinion, and when asked for it always gave good advice on her job and her career.

They seemed to be a match made in heaven and spent a glorious summer together. Whenever they didn't work, they were away from the city, on the lake, in a cabin in the woods, riding their bikes.

Jay had overcome his annoyance with the Intelligence unit for not backing him up during the Rodiger case, he gained self-confidence in his job. He even managed to stand up to Voight when Voight wanted to drown Pulpo. As much as Jay detested the criminal who had shot Antonio and killed other cops, he could not let Voight murder the man. Jay was afraid to lose his job over that, yet Hailey had supported him. And in the end, Voight accepted Jay's interference, Jay's moral compass. Jay was sure that without Hailey he wouldn't have had the courage to stand up to his boss.

Hailey was a patrol officer at the time, but it was already obvious that she would climb higher up the ladder. She was ambitious, passionate and capable, and her superiors noticed. And Jay's experience on the job helped her tremendously.

For no reason at all, however, both kept their relationship a secret from their colleagues. They never went to Molly's together, nor did they frequent other bars and restaurants where they might meet fellow cops. They didn't even discuss it, it just happened. Both felt safer when keeping their love life separate from their professional life.

Just like other couples, they had their fights, of course. But nothing major, basically everything was perfect.

One day, however, when Hailey arrived at Jay's place, Jay knew immediately that something was wrong. She didn't look into Jay's eyes, was unusually quiet and serious.

With a sigh she sat down on his couch.

A sick feeling in his stomach, Jay sat down beside Hailey. "Hon, what is it?" he asked softly. "What happened?"

Hailey looked down, and Jay could see that she fought tears. The sick feeling in his stomach grew worse. "Hailey, honey, what's wrong?"

"Jay, we need to talk," she finally looked up, looked into his eyes.

Oh no, that can't be good Jay thought. But he just nodded. "Sure, let's talk."

"You remember that I told you about the new job I applied for?"

"Sure, did you get the job?" Jay smiled. "You deserve it."

Hailey nodded and briefly smiled back at Jay. "I did."

"But…?"

"But I didn't know it's a special assignment."

"Okay…" Jay's eyes widened.

"They want me to go deep undercover," Hailey answered quietly. "For a long time, perhaps a year or longer. With no contact to anyone at home whatsoever, not my family, not my friends, not my boyfriend."

"I see," Jay said. He knew that Hailey was ambitious, and he loved her for it.

"Jay…"

"Shhh," Jay interrupted her. He needed to be strong, he couldn't stand in her way. Because he loved her, he couldn't hold her back. "Hailey, do you want that job?"

"Yes, Jay," an insecure smile.

"Then you must take it," Jay tried a brave smile, but failed miserably. Nevertheless, he continued, "Hailey, I hate to let you go, but you can't let this opportunity slip just because of me. You would never forgive me."

"But I'm in love with you, I don't want to lose you."

"And I'm in love with you, Hailey. I don't want to lose you either." Jay assured her. "And if fate or God or whatever wants us to be together, then we will be together eventually."

"You think?"

"I am sure of that," Jay answered, sounding more confident than he was. This was breaking his heart. "When does this assignment start?"

"In a week from now," Hailey answered meekly.

"Then let's make the best of this week, OK?" Jay tried a smile, which didn't turn out quite right. Hailey nodded and let herself fall into Jay's arms. She buried her head in his chest and let tears fall. Jay held her close, tried to be strong. Life could be cruel.

Today

On the way back to the precinct, Jay was unusually quiet, remembering that summer with Hailey, and the last week especially. It broke his heart that he had to let her go, but he was convinced it was the right thing to do.

Erin didn't notice, as she was going on and on about that insolent detective from Robbery-Homicide. How could she just kick them off their crime scene, how could she treat them and Voight like that?

Jay didn't answer.

"Hey, somehow this Detective Upton looked familiar," Erin suddenly said.

Jay flinched briefly, looked at her. "You think?"

"Or perhaps I took her for someone else," Erin immediately shrugged it off. It didn't matter to her.

Back in the office, Jay was still pondering about how to contact Hailey, when she suddenly stood right there in the office.

Unfortunately, she accidentally spilled coffee over Sergeant Platt's shirt because she was quite agitated, so her first meeting with the whole team was not what it should have been.

Jay felt sorry for her, wanted to jump to her side in support; yet he only gave her a quick look of reassurance, he wasn't sure she noticed before she headed for Voight's office.

And when she left Voight's office again after a few short minutes, Jay could tell she wasn't happy; she was furious.

Al glanced in Jay's direction, clearly remembering Hailey from back when they had met at Jay's apartment during the Rodiger case, but apart from a raised eyebrow, he didn't comment.

Thank God for Al, Jay thought.

He desperately wanted to follow Hailey downstairs to talk to her, but it would have been too obvious, he decided. It had to wait.