It was a small studio apartment in the heart of one of the poorer sections of D.C., close to the entrance to the subway. Don wished that he'd had the time to be impressed with how quickly Gibbs had obtained the warrant to get in, but that would have to wait for a better day. At the moment, both teams had more important things to work on.
Don took the steps two at a time, Gibbs on his heels, both with handguns clasped in firm grasps. This was not just any raid. This was national security, never mind that there was a brotherly genius involved.
Gibbs seemed to feel the same way. The pair flattened themselves against the edges of the doorframe, the rest of their combined teams further down the hall and ready to provide back up. Don held up his hand with a silent count: three, two, one—
Blam! Gibbs kicked down the door with one over-powered foot.
"Federal agents!" Don yelled, barreling in and dropping to his knee in case someone got the bright idea to shoot back.
Not necessary. The place was empty. Don and Gibbs had the studio apartment cleared before the rest could hustle in after them. There was nothing to hide behind. There was only a single stuffed chair with a table beside it, and a set of two straight chairs with a small table to eat on in the entire apartment. A bed stood in the corner.
"Toss it," Gibbs ordered curtly, even as the group began to spread out to do just that.
"Empty closet," David reported. "No clothes, nothing."
"Bed hasn't been slept in."
"There are no dishes in the cabinets in the kitchen."
"A drop," Gibbs realized grimly. "This Dr. Levinger is involved somehow. Everyone, back off; let's get Forensics in here for prints and whatever else they can find."
"No time." Of that, Don was certain. "Look at this." He pointed to the small table, the cheap lamp overshadowing the fake wood surface. On the table was a small black device: a cell phone.
"Prints," Gibbs ordered. "DiNozzo."
"Got my kit, boss."
"We need to get this back to some place that we can work," Don realized. "Gibbs, this is a throwaway cell. We need to pull the numbers that this thing called and was called from."
"And we need to do it now," Gibbs agreed.
"Don't do it."
Charlie cringed. McGee—no sense in referring to his fellow captive as 'Penfield' any longer. The cat was out of the bag—was watching him, his face drawn with pain. The agent looked pale, too; blood loss, no doubt. Charlie was no expert in medical affairs, but he was afraid that Special Agent McGee might not live long enough to be tortured. A variation on Prisoner's Dilemma, Charlie thought wildly. Which scenario would yield the best outcome: torture or death?
This was the one time in his life that Charlie didn't want to do the math.
"Don't do what?"
"You don't lie very well. Even I can tell that." McGee shifted, let out a hiss when his leg objected in no uncertain terms.
"I can't let them—"
"You have no choice." McGee cut him off. "You can't let them have the information." He stared at Charlie. "You've solved it, haven't you?"
"No—"
"You lie worse than I do," McGee told him, "which is pretty bad. It's worse than bad, Professor Eppes, which means that we have to put an end to this right now."
"I can—"
"No, you can't." McGee was brusque. "Can you honestly stand there and tell me that you are going to be able to stand by and watch what they do? Honestly?"
Charlie couldn't look at his fellow captive. His voice was low. "No."
"Right." McGee didn't gloat over his victory, and Charlie was grateful for that much. McGee went on. "You have to get out of here. Now. Right now. Understand?"
"But—"
"There are no 'buts' about it, Professor Eppes." McGee was firm, despite the situation. "If they come in here again, they will have the information they need and thousands if not millions of Americans will die. We have," and McGee looked at his watch, "less than twenty minutes before our two hours are up. It's now or never, professor."
That led to the next problem. "How?" Charlie asked, trying not to sound plaintive. "There's not way I can break the window quietly, and trying to shimmy out will take too long. There's a man stationed outside the door. He'll hear me."
"Right." McGee had already solved that problem. "Here's what we're going to do."
There was at least a thousand calls made from the throwaway cell phone, and each one was listed on the screen in the bullpen of the NCIS headquarters. The screen held an incomprehensible cacophony of numbers.
Abby's voice floated in over the speaker phone. "Gibbs, I can track down these numbers but it looks like each one is different. I've already done the fast scan; only two are to the same numbers. All the rest is a jumble."
Don was grim. "It will take a hundred men ten hours to visit every address, and that's assuming that each call went to an address. Some of those will have gone to other cell phones, and those people could be anywhere. We don't have time for this."
"This is where we usually call in Charlie," Colby said, equally as unhappy. "These are numbers; patterns. This is what he lives for."
David nodded. "He could search for the pattern in those numbers, see if anything pops up." He looked away. "Dammit, we could use Charlie right now!"
That triggered something in the two team leaders. They looked each other, light flickering in two sets of eyes.
"Penfield."
"Ready?" McGee almost whispered it.
Charlie nodded. He wasn't really ready, but they were rapidly running out of time. It was now or never. He raised the heavy mug that he'd liberated from the kitchenette. The mug was wrapped in a dish towel to try to muffle the sound as much as possible.
It worked. Standing on a chair, Charlie slammed the mug against the pane of glass, and the window shattered into more than a thousand pieces. He tossed the mug away, and hoisted himself up to the window, trying to ignore the sharp edges cutting into the palms of his hands.
The man outside the door to the suite heard the commotion. Shouting to his comrades upstairs, he tried to open the door.
McGee was prepared for that. With Charlie's help, he had limped over to the door—almost passing out twice on the way, but McGee would be happy to overlook that little setback—and shoved a chair underneath the doorknob, preventing the man from bursting in on them.
Not for long. The straight backed chair was flimsy, and collapsed under the onslaught. The door whipped open, destroying the chair into splinters to join the shattered glass on the floor. The man darted into the room.
McGee was ready for that, too. There was a second mug, and it was in McGee's fist and it wasn't covered with a dish towel. McGee brought the mug onto the man's head, and the kidnapper collapsed as if McGee had injected him with the same joy juice that had been used when bringing the pair of code-breakers here.
McGee looked up. Professor Eppes had slithered through the broken window. There were bleeding scratches across his torso, but that was secondary. "Go!"
"You—"
"I'll be fine," McGee lied. "I'm the closest thing they've got left for a cipher analyst. Go!"
Charlie ran.
Colby glowered at the man behind the one way glass. "I'd've killed him by now."
Ziva's glare was equally as daunting. "I agree. The man is a pig. He whines."
The man in question was tall, with mousy brown hair that was slicked back out of his way. His sport jacket bore elbow pads and—worse—the elbow pads looked worn. The elbow pads looked used. There were spectacles for the eyes, but those were for show. Likewise for show was the large easel of paper with several nondescript equations scribbled on the top bearing equally as nondescript letters of a vaguely Greek origin. The laptop computer on the table in the interrogation room was humming frantically, its 'working' light flaring brightly enough to compare it to a star going nova as it attempted to keep up with the calculations required of it.
Tony DiNozzo had been elected to be the man's keeper. The pair outside the glass admired his self-control as he plastered the smile onto his face yet again. "I can almost see where you're going with that," he lied brightly.
Professor Marshall Penfield beamed. "Did you hear my lecture on Discrimination between Partial Populations? I knew that there would be a practical application to this. Eppesey argued with me, but as you can see: I was right." He looked around. "Where's that computer technician you assigned to me? Why isn't he here yet? I can't do all the computer work myself. This is the important part, here on the paper."
"He was delayed." Damn, doing a lot of lying today. If I tell this guy that he's actually tracking down the 'computer tech' who got himself kidnapped with 'Eppesey', he'll only throw a hissy fit. "He'll be along soon, I'm sure."
"If he doesn't get here soon, we won't need him," Penfield sniped.
Really? Then why did you say that you needed him in the first place?
"It's time for a map," Penfield said suddenly.
DiNozzo jerked around. "A map?"
"Yes. A map. What did you think that I said?" Testily.
"You think you know where they are?" DiNozzo grabbed the paper map from the corner of the room and spread it out onto the table in front of the mathematician. Yes! This slice of life may be coming to a merciful end.
"Of course I don't know where they are! If I did, would we be going through all this foolishness?" Penfield snatched the map from DiNozzo's hands and twirled it around on the table so that it was facing him instead of DiNozzo. "I need push pins. How can I designate the addresses if I don't have push pins?"
"Right here." DiNozzo was prepared. He placed the laptop onto the table beside the map, using its weight to hold down one paper end and positioning the screen so that the coordinates were visible.
Penfield tried to insert a pin onto the map, using the table as the background. Unfortunately, the table was a hard surface used to the banging about of perpetrators and low life types, and refused to allow anything as miniscule as a push pin to gain purchase on its stained table top surface. "It doesn't work."
"Here. Let me try." DiNozzo pushed at the pin, with as little luck.
"I need a cork board," Penfield announced. "Something that I can push these pins into. Get me a cork board."
"We don't have them here in NCIS headquarters," DiNozzo said, trying to stay patient and calm. "We haven't used them for ten years."
"Well, go and get one! For heaven's sake, we're trying to save Eppes's life here, man! We can't let something as foolish as a cork board stand in the way of a man's life, can we?"
"I've seen worse things," DiNozzo muttered under his breath, knowing that even under the best circumstances it would take someone at least half an hour to run out to the nearest office supply store and hope that they had a large cork board in stock. He forced the hopeful smile back onto his features, ignoring the fact that the expression wouldn't come anywhere close to his eyes. Penfield won't notice, he rationalized. "Tell you what: let's use this yellow highlighter. We'll just mark up the map like this—"
"You've ruined it!" Penfield all but shrieked. "Do you realize that we can never use this map again? Not with these marks on it! You've wasted it! Think of all the trees that died to make this map!"
"Name one—" DiNozzo started to snap back before catching himself. And I thought McGeek was bad. "It's all right, professor. We can get another one, and we'll recycle this paper when we're through with it. Look," he cajoled, swiveling the map around so that he could view it himself, "we've got this one spot marked. How about another?"
Penfield sniffed. "Fourth and Vine. That's assuming this map is accurate."
That's assuming your calculations are accurate. Is Professor Eppes this bad? I give the FBI team a lot of credit for self-control if he is. "We'll do the best we can," DiNozzo said, trying to ooze reassurance. "How about the next one?"
Bit by bit, DiNozzo cozened Penfield into applying the details of what he had learned onto the paper map of D.C. and the surrounding suburbs. There were false markings and plenty of Penfield-sized screeches when a mistake was made—obviously all due to DiNozzo's incompetence, for Penfield was clearly too brilliant to make an error—but slowly the yellow marks began to take on a distinct pattern.
"It's looking like—"
"No, it isn't," Penfield told him in no uncertain terms. "More data! More data! That's what I always say. You can never go wrong with more data. Add 1434 Union St," he instructed.
A shadow darkened the table with the map, and DiNozzo looked up, prepared to be grateful to whoever was interrupting his odious task. Two shadows, actually; both Gibbs and Special Agent Eppes were intervening.
"Got anything, DiNozzo?"
"No, he doesn't," Penfield told them testily. "I do. Look: these markings are clustered near Furlong Ave. And Fourth St. And Long Street, and half a dozen other equally probable locations. We've plotted the sites to which the calls were made, Special Agent Gibbs. A number of them were to areas in western states, and those I've jotted down on this paper over here, in case we need to expand our search area, but—"
"No, wait." Don stared at the scattering of yellow dots on the paper map of D.C. and the surrounding area. Something squirmed inside his brain, reminding him of something that his geeky brother had told him. How long ago had it been? Hadn't it been sometime when Charlie had first demonstrated how math could help nail a perp? Something about vector analysis?
"There simply isn't enough data," Penfield complained. "Each of these sites has nothing to recommend it over the others; the quantity of calls made to those sites is equivalent in every way. I simply cannot give you more accuracy if you do not give me more data points to work with."
"Eppes?" Gibbs knew that his counterpart was onto something.
Don touched the map, letting his finger slide from mark to mark, skimming the yellow points that showed where each call from Dr. Levinger's throwaway cell had gone to. The highlighted sites were in a roughly oblong shape, a cloud of yellow dotting a suburban area in one corner of the map. Don tried to imagine what the neighborhood looked like, drinking in the meager details that the map provided: a slender line of blue indicated a finger of the Potamac lurked nearby. The roads on the map in this corner were relatively sparse, which meant that the area was either an upscale neighborhood with a lot of property for the ultra-expensive capitol region or that it was more rural and further away from D.C. than it looked like on this map. Neither scenario helped; the dots were—to use a term better suited to emergence from Charlie's mouth—rather equidistant from each other, positioned in a rough oval.
It touched a chord. There was something here, something that was screaming, 'notice me! Notice me!" There was an answer, if only he could see it—there!
It was Charlie. It was Charlie, standing in Don's own office, stabbing his finger at a map plastered onto an electronic screen, pointing out how to determine the location of the unknown. It was Charlie using the example of a sprinkler: "You can see the droplets of water," he had said, "and you can see where they land. By knowing where they land, you can determine from where they originated." Then Charlie had gone on to the really important piece: "You can determine where the suspect—"
Don cut the thought off right there. "Vector analysis," he said.
Penfield's ears perked up. "Vector anal—" He broke off, interrupting himself. "Don't be absurd, Eppes. That's just like something that your brother would say. There are far better ways to handle this puzzle. Get out of my way," he ordered, pushing Don back even though neither Don nor anyone else in the room was obstructing the two inch path between the mathematician and the table with the map. "Get out of my way," he repeated querulously. "I have work to do." He bent down to the map once again, snatching the laptop with the calculations from DiNozzo's grasp.
Outside the window, Ziva observed the scene, glowering. "Can he do this?" she asked Colby. "Can he actually find McGee and your consultant?"
Colby shrugged grimly. "He's no Charlie Eppes."