Author's note: I'd intended to write this all in one shot, but it got far too long and had a rather natural break. So, keep an eye out for part two before long.

I've missed writing for this fandom. Glad to be back! Hope you enjoy this…

Code Black

Part One

It was about to be a painfully boring few hours.

JJ said as much to Emily as they crossed the big sliding doors into the ER.

They were fine.

There had been a jarring but insignificant collision between their car and that of the suspect they were chasing.

They were both convinced they were fine.

Hotch had insisted that they likely had concussions, which meant a CT scan for them both.

And since any injuries they might have were minor at worst, there would be an undoubtedly long wait.

Checking in with the triage nurse, they thanked the uniformed officer who had dropped them off and figuratively 'took a number'.

They dropped side-by-side into hard plastic chairs and shared a rueful, knowing half-smile.

"Twenty bucks says we're not out of here for five hours," Emily offered.

"Suckers bet," JJ returned.

Emily nodded, acknowledged:

"We've both been here before."

"At least we're home this time," JJ pointed out. "Not holding everyone up in some hotel."

Emily was quiet a moment, then she commented:

"They don't mention this kind of thing in the brochures."

JJ met her eyes.

They'd mostly avoided this topic up until now.

But she suspected it was on both of their minds.

"Do you ever regret it?" JJ asked now. "Coming back?"

Emily rubbed her neck, leaned her head against the wall behind her chair.

"There's no short answer to that question."

"We've got the time."

Emily was quiet. Then she turned the tables:

"You first."

JJ took a moment at that.

Because the truth was, she wondered.

Some days, when she had to stare a particularly sadistic killer in the eye, or kiss her son goodbye for what was likely to be several days…

Sometimes she wondered.

But that was heavy.

And she wasn't sure she wanted to dive into it just yet.

"I used to report to a supervisor who thought he wasn't sexist just because he loved his wife," she said rather flippantly. Before Emily could ask about that, JJ added: "But I also hadn't strapped on Kevlar in months."

"A good thing in your book?" Emily prompted.

"What, did I miss the adrenaline?" JJ questioned, and at Emily's nod, she gave her a tit-for-tat response. "You first."

Emily smiled an amused smile, thought it over.

"I missed the people." She paused, then: "I missed the satisfaction."

Before JJ could respond, a surprising thing happened.

A nurse called their names, and a moment later, they were on their way.

…

"Would've been my twenty bucks," JJ noted, as Emily was about to go ahead of her into radiology.

Emily shot her a look:

"Would'a, could'a, should'a, JJ."

With a half-grin, she disappeared behind the door with the nurse, and JJ took a seat in the hallway to wait her turn.

A few minutes passed quietly, and JJ felt her eyes start to flutter closed.

It had been an early morning, and a busy week, and maybe she deserved a moment's rest… right here in the hall…

She wasn't sure if she nodded off or not, but suddenly there was an announcement over the loud speaker:

"Code black. We have a code black situation in the ER. I repeat, we have a code black situation in the ER."

JJ didn't know what 'code black' meant.

She did know how to listen for vocal cues.

And the woman making the announcement, she'd sounded scared.

JJ stood, looked around.

Two doctors rushed past her.

Then the door behind her opened, and a doctor or technician moved past her, followed by a befuddled Emily.

Emily met JJ's eyes:

"I don't know what a 'code black' is, but -"

"But why are we hearing about it up here?" JJ filled in.

Emily's face said 'uh, yeah'.

And JJ moved to the currently abandoned nurses' station a few feet down the hall, glanced around to see that there was no one available to them, and rounded the desk.

She quickly found a code listing, posted on the wall by the main desk.

She scanned quickly to 'black'.

And read aloud:

"Violent person on premises."

Emily met her eyes again.

"They said ER?"

"They said ER," JJ confirmed.

They were already walking as they nodded in silent agreement, heading in the direction of the chaos.

…

"I understand that, Sir. I'm sure you're all very well trained and fully qualified," JJ was explaining to the hospital's Head of Security. "But we deal with violent individuals every day, and we're offering our help here. That's all I'm saying."

Emily watched in mind annoyance.

Didn't this guy get that he needed help?

On the other side of a pair of sliding glass doors, a sweating, pacing and undeniably desperate young man was holding over a dozen hostages with a security guard's gun.

JJ hadn't made that point – that it was one of Security's own men who had lost his weapon to this crazed kid.

Emily would have.

But that was probably why no one ever suggested she should handle a press conference.

"You're here as patients. Whatever help we need, we'll get from arriving authorities," the bushy-browed Head of Security was insisting to JJ.

"They'll determine this is a hostage situation and in all likelihood call on our team," JJ told him gently. "I'm asking you to let us get a head start on this. Before anyone gets shot."

Stress was etched on the man's face.

He didn't want to make the wrong choice, Emily could see.

She knew JJ could see it, too, because she stopped talking.

They both waited.

Sometimes, once you caught that look on someone's face, it was like clockwork.

Sure enough, a matter of seconds later, he turned to face them both.

"What do you need?"

"Let's start with access," Emily told him.

And it was in that moment that she felt her first flash of fear.

…

They spoke to Hotch before slipping through a back entrance and into the danger zone that was the ER.

"This will go straight to SWAT," Hotch said to them both over speakerphone. "We might get the call to assist and we might not. Either way, we'll be there in twenty."

"That's twenty minutes for somebody to get shot," Emily pointed out.

They could hear Hotch sigh.

"You're unarmed," he noted.

"So is everybody else in there," JJ pointed out.

Hotch went silent. Then:

"You can both confirm to me that you've had absolutely no ill effects from the crash?"

"None," they both said in unison.

"No headaches, no dizziness -"

"Nothing," Emily insisted.

"If you do this," Hotch started, emphasizing the 'if', "Experience wins out. Emily takes point."

"Got it," JJ told him, nodding even though he couldn't see her.

"Drug seeking is an obvious possible stressor," Hotch told them. "He could also be a former patient, possibly a psychiatric patient. Or he might have a problem with some particular employee. Try to narrow it down, and we'll try to find a way to communicate when we get there." He stopped, then added: "Technically, I can't tell you to do or not to do this."

Emily and JJ shared a look.

There was no question.

Hotch must have known, because after another moment of silence, he said simply:

"Be careful."

And the line went dead.

…

They were able to slip in unnoticed, down a back stairwell and into the fray.

They moved slowly until they were with a handful of patients – one of three groupings of hostages – behind the young man with the gun.

He couldn't have been more than eighteen, a thin white kid in an ancient denim jacket, with dark, unruly hair that snuck over his ears - and shaking hands.

Shaking hands weren't good.

Neither was the way he was whispering to the nurse he had in his grasp.

She was young – in her twenties – and terrified, and though they couldn't make out what he was whispering to her, the snarl on his face wasn't good.

Emily had wanted to take more time, take him in, formulate a theory and a plan.

But his finger looked to be tightening on the trigger.

So she stood up.

"Can I help you?" she asked clearly and calmly.

He whirled on her.

She was vaguely aware that her heart was beating fast.

"I would really like to help you," she told him. "Can I do that?"

"Nobody can do that," the kid muttered.

He looked heartbroken.

Emily needed to know why.

"Did something happen to you? Here?"

"Just shut up," the kid told her. Then he all but growled as he pushed the young nurse to the ground.

"You don't need to hurt her," Emily told him. "You just need to let me help you."

"You don't know what she did," the boy insisted.

"I'll know if you tell me," Emily offered. "Why don't you tell me."

He was silent for a moment, pacing a few feet away and then back.

"I don't know what to do," he admitted. "I can't work it out. It's like the fifth when I was a kid…"

"The fifth what?" Emily asked him.

But he sunk to the ground against the admit desk, chewing the fingernails of his free hand.

The gun remained trained on the young nurse and the few patients in the same general vicinity.

Emily stole a glance at JJ, who caught her eye and nodded her head to the left.

Emily followed the gesture, and spotted a vending machine.

It wasn't a bad idea.

"Are you hungry? Thirsty?" she asked the boy.

He looked up, seemed almost confused by the question.

"There's a vending machine, just across the room," Emily explained gently. "You can see me the whole time. I'd like to get us some water."

He barely nodded, but it was enough.

Emily moved for the machine, and realized her own hands were slightly shaky as she collected change from the assembled hostages and distributed water.

Her legs were feeling shaky, too, as she approached the kid.

She was acutely aware of her lack of a vest.

She held out a bottle.

It took him a moment, but he accepted it.

And he offered quietly:

"I just wanted to stop her."

He met her eyes, and Emily seized the opportunity for a small victory:

"What's your name?"

"Adam," he told her.

And she nodded, told him:

"Okay."

…

Emily seemed to be making headway.

She was making good use out of knowing the unsub's name.

Every time she said it, JJ could feel him starting to trust her.

That was good.

What wasn't good was that JJ thought she knew what was going on.

She'd listened to the unsub's words to Emily.

She thought she'd figured it out.

She didn't think Emily had, and she wasn't sure how to approach her.

Telegraphing their status as agents would be bad.

And so all she could do was watch.

Five minutes passed, then ten.

JJ started to feel calmer.

She was starting to think that maybe it wouldn't matter whether Emily knew what had started this or not.

The boy – Adam – he was listening to Emily now.

They were speaking so quietly that JJ couldn't hear what was being said.

She watched intently, encouraged when the boy actually let Emily reach out and rub his back.

But JJ should have been watching something else.

She should have been eyeing the group of hostages.

She should have known better.

Should have realized that they were stressed to the max, and they were currently the wild card.

She realized it too late, when a burly man who'd been keeping himself between the unsub and his son made a choice.

He made a play for the gun.

There was a lightning-quick skirmish.

Then a gunshot boomed –

And Emily crumpled to the ground.

…