A/N: Hello, everyone!

I haven't disappeared. I've been busy. Writing this story. It is completely done save for the epilogue, which will probably be done by the end of the weekend. So first, let me thank my beta, Maria Binger, who patiently looked over everything for me, put up with my insane writing spree, and was great for bouncing all my ideas off of. As I explained to her, I was afraid of writing a serious crossover involving characters from a TV show, since I don't think you get the same insights as you do with a book (or I just prefer books), so bear with me on this one. Let me know how I'm doing, and I promise I'll upload a new chapter every 3 days. With the epilogue it's 15 chapters, so if I stick to my schedule I'll have written and posted this whole story in less than two months. I did it this way so I don't try working on four stories at once again, and I kind of like this way of writing. I'm doing it from now on, once my other stories are all finished.

So, fans of my other stories, look for updates coming soon. New readers, welcome, and I hope it's up to your expectations.

Before we get to the story, please enjoy the disclaimer: I own nothing, I'm not making profit, all characters you may recognize are the property of JKR, CBS, and their various affiliates.

Enjoy, and please review.

It may be hard for an egg to turn into a bird: it would be a jolly sight harder for it to learn to fly while remaining an egg. We are like eggs at present. And you cannot go on indefinitely being just an ordinary, decent egg. We must be hatched or go bad.

-C. S. Lewis

This scene is getting old, Reid thought to himself.

He slid past a burly officer guarding the door, stepping into the familiar scene. A cheap hotel room. A dead body laying across the bed. This one is young, and wearing a t-shirt from the nearby college. The medical examiner will be stumped yet again. No cause of death. Just a seemingly healthy young man keeling over dead. They would check for forensic evidence, but there will be none.

There's not much rhyme or reason to how often it happens, but there have been seventeen since they had gotten there. Twenty four in total. Sometimes the scene changes. The room isn't always a cheap hotel room. Occasionally it's a bedroom in a nice house. Or in a run down house. Or an apartment. Once it was in a van. The faces are always male, but that's pretty much it. They range in age from eighteen to seventy one. Black, white, Asian, Hispanic, and one Native American. Some have brown eyes, some blue, some hazel, two gray. Some have facial hair, some are clean shaven. Some have college degrees, some are high school dropouts. Some are married, some are single, there's a widower in the group. Some have money, some are living paycheck to paycheck. They all drove different types and colors of cars. They came from all around Chicago and the nearby suburbs. The only thing that links these men is the fact they are men, they are dead in a very mysterious manner, and the rooms are locked from the inside, with no evidence of someone leaving out a window.

He had spent hours searching, trying to find something, anything, that might help them figure things out. All these men were last seen in bars, but no one remembers who they last talked to, or when they left and with whom. The rooms offer nothing, they are completely clean. The bodies offer nothing, no telltale bullet holes, no traces of poison, blood alcohol content that would be lethal, no reason for these men to be dead. A couple of these may have never attracted attention, but this many is too much for coincidence.

Hours of searching had revealed a couple cases with similar MOs. The most high-profile of these was in England nearly sixty years ago. A man and his parents had been found dead in their home, horror written across their faces, no cause of death ever found. And the room had been locked from the inside. Same as all these.

The city was in a near panic. Bars had reported their attendance and sales dropping like stones. Taxi drivers had been doubling up, willing to split costs and work extra shifts than be caught riding alone. Men have been moving in a pack rather than individually. Even the guys in the tougher parts of the city have been weary of moving alone. But people screw up. Plans fall through. And alcohol is a great way to make people forget how cautious they were being about something.

And so it continued. Sometimes it was five days between murders. Sometimes one. It seemed to be escalating. And they trooped out to each new body, carrying all their gear to look for that piece of evidence that was never there. Just one little hint to break the case. Anything.

There had never been so much pressure on them to create a profile, and they had never been as unable to do their jobs as they were on this case. The unsub gave them nothing to work with. They argued even the most basic points, with half the team thinking it was obviously a woman, the other half saying that historically it was more likely to be a man. The question had been raised on whether there was even a killer here.

Spending the majority of their time around each other arguing was starting to become draining, and they couldn't wait until they got to break for the day and get away from each other. They all handled their alone time differently- reading, dining alone, but they stayed away from bars, and treated every new person with suspicion.

Spencer Reid looked like he might be about to crack from the stress. He had tried color-coding his maps in almost every way imaginable- by race, by hair color, by age, by occupation, looking for anything, but no pattern stood out to him. There was no comfort zone, anywhere and everywhere seemed to be the unsub's preference. There was no way to predict where the next victim might be picked up from or found, every time he caught a glimpse of a pattern the unsub threw him a curveball. Some of the crime scenes were blocks from the bars where the men were last seen, some were across the city.

"What do you think, Reid?" Derek Morgan asked him.

"I think we need to empty the city of Chicago," he muttered back under his breath.

"Short of that."

"Close all the bars."

"Anything about the scene?"

"It appears to be the same as all the other ones. Dead body, no visible cause of death, door locked and bolted from the inside, no evidence. You know this. What do you want me to tell you?" he snapped. He slammed his notebook shut and walked out. There was nothing for him there, let the Chicago PD take care of it. It was ten-thirty at night, and he had been working since three in the morning. He had done seventeen-plus hour days since they had got to Chicago, and he was the last one to throw in the towel and leave a scene early to get some time to himself. But it was that time.

"I'll see you in the morning," he muttered as he strode past Hotchner.

"I'll call if I need you," he replied in a low voice.

He mumbled an unintelligible response, but his phone would be turned off as soon as possible. This was his time, to hell with going back to the same damn scene. He walked around the corner and hailed a cab. As he climbed in the backseat he noted there were two people in the front, and a crudely installed surveillance camera recording him.

"Is there a decent place to eat open at this time of night?" he asked sharply.

"What's your food preference?" the driver asked.

"Something quiet. Anything quiet."

They drove for a while before coming to a stop in front of an Italian restaurant. He paid the drivers, tipped a couple extra dollars, and hurried inside. The dining room was dimly lit, half-full, with a quiet hum of dozens of hushed conversations. A hostess appeared quickly, and as they walked through the dining room he could tell many of the conversations were about the killer lurking somewhere in the city. He was seated at a booth concealed in a nook, and he sat with his back against the high wall and felt comfortable. For the first time since he got to Chicago he didn't feel like he needed to keep watching over his shoulder.

He watched the diners as he slowly finished a bowl of soup and started waiting for his entree. He allowed his mind to stray from bodies and unsubs and crime in general. He started to think about his mother. He hadn't written her in three days, and it was killing him inside. He would have to make sure he wrote her a long letter before...

The soft clicking of heels on the hardwood floor was his first alert that someone was coming. At first he thought it was the waitress, but he remembered she was wearing sneakers. Before he had a chance to guess again a pretty brunette woman slid into the bench facing him. She was dressed to fit in- a pair of nice slacks, a black top, and a nondescript purse. Her brown eyes were warm yet stern, and it was easy to see that she was feeling some decent level of stress. He stared at her, mouth slightly open, a pit growing in his stomach.

"It would help us to not draw attention if you stop looking at me like I'm about to kill you. I assure you that I'm not," she said in a low voice, her smooth British accent coming through.

"I... I'm... I'm sorry," he muttered, biting his lips together to avoid staring at her open mouthed, his eyes scanning her, trying to remember every detail he possibly could.

"I understand how my presence is probably making you nervous," she smiled at him, like he was nothing more than an old friend. "The whole situation is rather unorthodox. However, you and I are striving for the same goals."

"What goals would those be?" he asked.

"Catching this... what did your team call it? Unsub. I like that. I'll probably start calling them that when I get back to the Ministry."

"You're hunting the unsub, too?" he asked, trying to conceal his shock.

"I, like you, have been called in especially to work on this case. We have fifteen Aurors working on this case, and whoever they are they're making things difficult. Normally they would be bragging, or at the least be giving us a hint as to why they are . All we can figure out is they're probably anti-Muggle, since that's all they've been killing."

He could feel the confusion across his face. None of what was coming out of this woman's mouth made sense, but he couldn't help but think that whatever nonsense she was talking was the key in finding their unsub.

"You've got quite the impressive set of boards up in the office at police headquarters. Very organized. I like that. Two boards dedicated to victims, one with the map, one dedicated to possible links between victims. But that last one is pretty blank."

"That's where we'd put the known information about the unsub," he muttered, becoming more scared by the second. This woman had been in their work room? When? How? It was in the middle of Police Headquarters. Surrounded twenty-four hours a day by policemen who had been told that no one but the BAU team was allowed in. They had been working together enough all the police knew the team members, certainly someone must have noticed this woman standing in there, studying their work boards.

"You're trying to figure it out, and I promise you, the truth is beyond anything you could guess," she chuckled.

"What do you want?" he managed.

"Your help," she said casually, pretending to look over a wine list. "We're stumped, but Americans have a tendency to train their Aurors to act quickly and know how to capture rather than use logic to figure things out. That's why they brought me in, but I could use some help. Someone to bounce ideas off of who isn't a complete git so to speak. I've watched your team for the last three crime scenes..."

He shuddered visibly. He would have remembered this woman if he had seen her before.

"I'm trained in not being seen, so don't beat yourself up for not noticing me. I think you and I would make the best team. I can't explain everything to the whole group, I don't want to work with a big team, that will only complicate things. The fewer people know about me, the better. I want to work together, away from both our teams, somewhere where we can think freely."

"How am I supposed to know that you are really part of some team, and not the unsub?"

"That's a more than fair assumption. I haven't told you much of anything you can verify. What can I tell you that would put you more at-ease about meeting with me?"

"We could start with a name."

"Hermione Granger," she smiled warmly. "I'd shake your hand, but seeing as we've been sitting here a good five minutes that may look a little strange."

He shook his head, struggling to find what to ask.

"If it would make you more comfortable, I'll give you two things. The first will be waiting for you in your hotel room. Check the drawer of the night table on the right hand side of your bed. There will be a little more detailed information about me there, as well as my address and several photos. You can run those through whatever programs you can think of, it'll verify that I am who I say I am. I live among Muggles, so my drivers license and all that should be accessible. I know you can't really trust what I give you, but hopefully this will spark enough confidence that you'll agree to meet in public."

"And the second thing?"

"I'll tell you how they died. You won't believe it. You'll check a couple dozen sources for information before you'll even entertain the thought I might be telling the truth. There will always be a hint of doubt about it unless you see it, and I'll do my best to avoid using it in front of you. But I'll tell you anyways."

"What is it?" he asked, suddenly becoming aware of his position. He had moved as far forward as he could, leaning towards her, excited with the anticipation of knowing the cause of death that had eluded them thus far. His fingers were digging into the seat, and he couldn't tear his gaze from her.

"You may want to calm down," she muttered with a smirk. "You look just about ready to jump across the table."

He quickly scooted back against the seat, banging his back against the wall.

"Better. After I leave there will be a card under your napkin. On that card will be the information I just promised. If you will agree to meet with me, write the time and the place on the back of that card. You don't need to do anything beyond that. I'll get the message, and I'll be there."

"How long will it take you to get there?" he said, his eyes now staring at her hands, waiting for the card to get deposited under his napkin.

"Five minutes at most."

"From anywhere in the city?"

"Five minutes," she repeated.

The waitress suddenly appeared, holding his dinner. "Oh!" she said, looking at Hermione. "I didn't know you were going to be meeting someone. Did you need a menu?"

"No, I was just on my way out," Hermione replied, gathering her purse. "I just wanted to say hi to an old colleague." She stood, and held her hand out to Spencer, who shook it, looking disappointed. He didn't see her slide him the card, and now it looked like she was leaving without giving him his promised reward. "We'll have to meet up properly sometime soon," she finished, eyes seeking his.

"Of course," he stammered. "I'll drop you a line."

"Goodnight, Mr. Reid," she nodded, then turned and started walking towards the door. Without a word to the waitress he lunged for his napkin, knocking it to the side. The card was there. His eyes shot back up to get a view of her retreating back, but she was gone. He grabbed the card and turned it over. There was no long explanation, just two words written in an elegant script:

Avada Kedavra

It may be hard for an egg to turn into a bird: it would be a jolly sight harder for it to learn to fly while remaining an egg. We are like eggs at present. And you cannot go on indefinitely being just an ordinary, decent egg. We must be hatched or go bad.

-C. S. Lewis