Warning: Deals with rape BUT there is nothing graphic and nothing actually written but this might make some people uncomfortable. If you don't like please don't read.
Authors Note: Ok, so this is my first 'Numb3rs' fanfiction so I hope that it's ok. If anyone is inclined please review and any constructive criticism, it is always appreciated :-). Ok, Charlie lovers; Charlie is a big part of this story although he does not appear in the first few chapters. I put this as I know from experience that people's perceptions of a story are made on the first chapter and who appears. But there will be a lot of Charlie, a lot of Don and a lot of Larry.
Thanks: I have to thank the wonderful ButtercupHarmony for beta'ing this and doing a fantastic job and for her transatlantic translations making these very American characters sound rather less British :-).
Disclaimer: If I own these characters, apart from the ones I've obviously made up, I'm a goldfish with my very own little red bicycle.

Chapter 1

Don stood in the conference room looking around at his assembled team. On the board behind him was a picture of a young man, short brown hair, badly beaten. He held in his hands, a whole pile of other pictures.

"Listen up. Meet Mitch Blain," he gestured to the photo on the board, "a sophomore at UCLA. He was raped and beaten yesterday evening by a man that appears to be making his way round the country."

Don moved closer to the board while still talking. Turning to the board he started pinning some of the other photos he was holding to it, listing the names of the men and the universities they attended as he did so.
"Michael Louck" Another beaten face with brown hair, this time cropped short. "freshman, Arkansas State. Daniel Redmond," longer slightly wavy brown hair again badly beaten, "senior, Emory University Atlanta."

Don moved away from the board and threw the rest of the photos onto one of the tables. David, Megan and Colby all reached for the photos, still listening to their boss as he talked.

"Guys, the list of victims is long. All at college, all 18 – 22, all brown haired, all brutally raped and beaten. After far too many of these cases an FBI agent in Chicago, recently transferred from Seattle, recognised similarites between two rape victims, one in each state. He started some research. There have now been suspected victims found over the past 19 years." Everyone in the office looked sharply at Don. "You heard right, 19 years, think about how old you were 19 years ago and then process that this guy has been rapping young men, boys, for that long. However, no one has yet been able to find anything on the actual attacker. It appears that the perpetrator changes campuses after each attack, taking a few colleges from the bigger cities in each state before moving onto the next. And now he's moved to ours."

Don looked around his team and noticed the visible anger Colby's eyes. Looking around the room he saw the same thing reflected in every face there.
"From a pattern that is becoming clearer as more cases are found, it looks like he's returning to colleges he attacked years earlier. These attacks appear to be happening in 10 year cycles. And if he's come to LA for now we have to assume the same to be true."
Don moved to stand directly in front of the board and looked at his team.
"I need all information on any rapes of brown haired students at any of the colleges in, and around, LA both past and present. There is still the possibility that Mr. Blain's attack has nothing to do with this case, is in fact just a coincidence, although I severally doubt it."

Don turned to Megan and David as they placed the photos they were holding back onto the table.
"Megan, David, I want you two to go to the hospital and see if there's any information that Mitch can give you that he hasn't already given the police. Anything he's only just remembered, anything that he might not have thought was important before."
Don then turned to Colby who sat a little straighter in his chair.
"Everyone else, I want you searching every database we've got to find any old rape cases that match, focus on 10 years ago, possibly even 20. If he is hitting the same colleges 10 years after a previous attack there's a possibility we can find out where he's heading before he gets there. I'm sure I don't need to remind you all that this is a very serious case and we need to catch this bastard before he hurts anyone else. Ok, go."

David and Colby moved towards the door along with everyone else, leaving Don and Megan alone. David stopped at the door to look at Megan, she held up a finger to indicate she'd be one minute and then turned back to Don. Megan stared at her friend and boss as he looked down at the photos on the table.

"Are you ok?" Don looked up sharply, not realising that he wasn't alone. "I fine, I want to catch this guy and I want to catch him quickly."
"We all do. Maybe we could get Charlie could help, maybe he could figure out…..hell I don't know, I barely understand what it is he does but it always seems to work." Don smiled at her, but the smile didn't quite reaching his eyes.
"I'd rather not get him involved in this."
"But if he can help…."
"He's a professor, what if it's one of his students next? I just don't want him involved if I can help it."
"Ok, but think about this, if one of his students is attacked don't you think he'd be angry to know that maybe he could have helped before it got to that stage?"
Don looked hard at Megan, knowing she was right. Finally he sighed.
"Let's see how today goes and maybe I'll consider asking his help if we've not gotten anywhere. This is just…...these are vicious attacks, I'd just rather he not be involved with this."

Megan stood up from where she'd been sitting and walked to the door. She turned back to look at Don.
"We'll catch him." She tried to reassure him, not too sure why she felt the need. The expression on Megan's face was so positive and determined when Don looked at her that he couldn't help but be caught up in her belief. They were going to catch him, and before he attacked anyone else.