The television show "Numb3rs," including the characters Don Eppes, Charlie Eppes, Alan Eppes, and Margaret Eppes, is copyrighted by CBS Paramount Network Television and Scott Free Productions. The television show "Supernatural," including the characters Sam Winchester, Dean Winchester, and John Winchester, is copyrighted by Warner Brothers Entertainment Inc.

The kid gave him a look that was so deeply grateful it was kind of pathetic. "That'd be great. Yeah, thanks. I appreciate it."

"It starts at 11, but it's just a block party, people will be drifting in and out until 3 or 4. You can get the address and directions from Joe. Joe, say hi to Anna for me."

"Will do. Wait, before you go, I have to show you pictures of my newest grandbaby."

"Got another good-looking one?" Smiling down at the pictures, Don still noticed Sam out of the corner of his eye. The kid dropped his cell phone in the trash as though he were still angry. But before he did, he punched a few buttons and held it to his ear, trying to hear again the voicemail that had so enraged him.

----------------------------------------------------------------

Actually, Don was surprised when Sam did show up for the party at 11:15, and a little chagrined. It suddenly struck him that, since Sam knew no one else, he was going to have to play host all afternoon. But he'd reckoned without two things: the ability of a kid who's moved around a lot to strike up fast acquaintanceships, and the maternal instinct of Margaret Eppes kicking in the moment she saw Sam's skinny arms and puppy-dog eyes. The next thing Don knew, Sam with sitting with several of the Eppeses' younger neighbors, making easy conversation as he balanced a mountainous plate of food on his knee, and Don felt free to join his dad for a quiet beer on the porch.

"Now that's a car," Alan Eppes said during a lull in their talk. He was watching a long black classic, polished to a blinding gleam, as it drove slowly along the street.

"That's an Impala?" Don said with an equally admiring look. "Sixty – "

"Sixty-seven. A beauty. Whoever owns that really knows how to fix up a car."

At the exact moment he said that, the car pulled over to an empty space at the curb and stopped. A solidly built, slightly graying man emerged from the passenger side even before the driver had shut the engine off.

"Ohh," said Don. "I have the feeling that this is the guy trying to reach Sam."

"The phone thrower?" A young man in a black leather jacket sprang out of the driver's door and the two started purposefully up the sidewalk. "His dad must be desperate to talk to him."

"Yeah, and Sam is pretty desperate not to talk."

"Well, I sympathize with the dad." Alan stood as the two visitors began crossing the lawn, but continued talking to Don through his smile. "But it would be nice not to have a fist fight at your mother's party."

"Copy that," Don said, also standing and smiling. Then, as the visitors reached the porch, "That's a beautiful car."

"Thanks," the younger man said, and the older man asked, "Is this the Eppes residence?"

"It is, I'm Alan Eppes. What can I do for you?"

The middle-aged man stepped up to shake Alan's hand, smiling pleasantly. The younger man, looking around watchfully, stayed a step to the rear. "I'm John Winchester, this is my son Dean. Joe Edwards told us that my son Sam might be here."

"Joe's a great guy, isn't he? How do you know him?" Alan was heartily friendly, and not moving.

"I don't. Sam told us he was working at the restaurant, and luckily we got there just as Joe was closing up. He told us where Sam might be. We've had a family emergency, and it's very important that I talk to him. I understand if you don't want party crashers, but would you mind if we spoke to him out here?"

If Alan had been looking for signs of a hot temper, clearly they weren't forthcoming. Quite the opposite: Don was suddenly reminded of a guest lecturer he'd heard at the FBI Academy, a man legendary in law enforcement for his skill in hunting serial killers and his ability to emotionally handle the job. John Winchester had the same persona, a quiet haggard toughness.

Don looked at Dean and was a little surprised to see that, as he'd been observing Dean's dad, Dean had been observing him.

Alan had obviously decided that the Winchesters passed muster. "What crashing? It's a block party. Come on in," he said, and led the way.

There were perhaps 30 people in the Eppeses' spacious back yard, sitting in conversational rings on the rented folding chairs or standing by the picnic table where a feast was laid out. On a nearby table, tubs of ice held bottles of tea, soda pop and beer. Don was amused at the way Dean's eyes lit up at the array of goodies. When he dropped the role of straight-faced aide-de-camp for his father, Dean was a good-looking guy with a boyish grin and rather hard eyes, probably catnip for girls; could that be a source of family strain, Don wondered?

John Winchester, undistracted by food, spotted Sam in one quick sweep of the yard and headed for him, Dean following. Don went along, just on the chance that things got too interesting, as did Alan.

Sam was listening with amusement to a guy telling a story with vigorous hand gestures, but when he spotted his father he excused himself. He met John and Dean a few steps away from the group of people he'd been with.

"We have to talk, son," John said.

"Good to see you too, Dad." Sam was quiet and controlled. "Pull up a chair. Have some potato salad."

"I'm serious."

"My birthday was great. Thanks. I almost have enough money saved for next year. Want to know what classes I'm going to be taking?"

"Don't be smart with me. This is an emergency."

"It's always an emergency. Dad, what's the point? I know what you're going to say and you know what I'm going to say. We'll start out talking, we'll end up bellowing." Sam glanced quickly at the people around them. "Let's just – let's don't and say we did."

"Sam, as a general rule I wouldn't butt in," Alan began, "but as a father, I understand – "

"Don?"

Don turned to see Charlie, and instantly lost all interest in the Winchester family drama. Charlie was literally pale. His eyes were shocked, his face vulnerable and childlike. He looked like the 10-year-old who'd been threatened by a ninth-grade bully for correcting him in class.

"Charlie? What is it, buddy? You look awful."

"I feel – I'm going to sit down." He looked around blankly for a chair, and Mr. Levinson from next door was standing there, chair in hand. Several people, in fact, were suddenly close, and Don had the feeling they knew something he didn't.

Charlie sat down. "There was a – meeting – some group or cult – at CalSci last night. They drank poison. The police don't know if it was mass suicide or murder-suicide. Four of them are dead."

"Margaret," Alan said in a low, urgent tone, which Mrs. Eppes caught from halfway across the yard.

Don looked around in disbelief. A few people were nodding, like Mr. Levinson. "It was all over the news this morning. I didn't really want to talk about it here, with children around."

"Group of kids committed suicide at CalSci last night," Alan murmured to Margaret.

"Dear God." The beautiful dark-haired woman, regardless of her pale blue outfit, dropped to her knees on the grass beside Charlie and put her hand on his arm. Charlie was buoyed a little by her presence; he smiled at her weakly.

"We haven't had the TV on this morning," Alan said almost apologetically. "We've been getting ready for the party."

"Do they know – " Margaret looked around – "was it a religious thing, a – "

"They really don't know much." A red-haired woman Don didn't recognize. "It wasn't just a student thing, there were other people involved. Someone said they called themselves the Hunt Club."

A flicker of motion in the corner of Don's eye. Sam Winchester had jerked his head around, and he and his father were gazing at each other with no hostility at all.

"Did you know any of them?" the Levinsons' teenage son asked.

"Two. Two of them were my students. One of them survived. The only survivor." Charlie looked up at Don with tears in his eyes. "This is beyond my comprehension."

Mr. Levinson gestured with his head, and he and his son moved a few yards away, followed by the others with finer feelings. The Winchesters, however, remained as though locked into place behind Don.

"The campus is closed. I've been talking to the police, well, waiting for them and talking to them. I tried answering their questions, but they had no information for me, or none that they would give me."

"They can't tell too much at a time like this," Margaret said gently. "They don't want to jump to conclusions, or want other people jumping to conclusions."

"But don't they see, the lack of data is more likely to lead to erroneous conclusions. Pam, the survivor, she was struggling in my class. I remember she frequently needed assistance during office hours. How can I know whether she – whether I was pushing too hard, she felt she couldn't – "

All three of the Eppses made sounds of dismay. "I've seen you teach, you're not like that," Margaret said, as Don said, "Nah, that's ridiculous!" and Alan said, "What would even make you think that, Charlie?"

"Because it was my classroom," Charlie said numbly. "The room where I taught Pam and Manuel. That's where they did it."

No wonder, Don thought. His little brother who sometimes seemed barely conscious of other people, no wonder he was so upset. Wakened from his beautiful dream of mathematical symmetry by an insane cult slamming his face into the messiness and occasional horror of human life. Don felt an irrational desire to go kick someone's butt.

"This is why I was pushing so hard to talk to Sam," John told Alan. His voice was gentle, soothing. "Something like this happens – you have kids the same age – you want to make sure they're safe."

Alan nodded.

"Have you talked to her?" Sam asked Charlie.

"Who?"

"Your student. Have you asked her why they picked your classroom?"

"No."

"Maybe you should."

"She's at Huntington Memorial. I doubt if they would – " Charlie shook his head. "No. Let's be honest. I don't think I want to know."

"But maybe you need to know." Sam pulled a chair over to sit facing Charlie, and Don had a strange feeling that he was watching someone much older and much more experienced than the kid he'd invited over. "Look, you know there's a 99 percent chance she'll say that the room was picked randomly."

"But there's not a 99 percent chance that the room was picked randomly. The odds of their having picked a room at random, but in which two of them had a class – "

"OK," Sam said with a grin, "not randomly, but with no thought of you or even the class. It was just a place everyone knew how to get to, or something like that."

"And if she said otherwise? That the room was associated with despair, or that they were trying to send a message – "

"They weren't, Charlie!" Margaret said, but somehow Sam's voice ruled: "Then you've got something to deal with. But you're dealing with something anyway. Uncertainty sucks."

Charlie nodded.

"I'd be willing to give you a lift," Dean said casually.

"I don't think – " Don began.

"You want to take shotgun in the Impala, Don?" Dean asked.

Frailty, thy name is Man before a classic automobile. "Um. Only if Charlie actually wants to go."

"I think I do. Yes. I want to understand this."

"You know you'll probably never really understand why they did it," Margaret said. "The human mind can't be reduced to a set of algorithms."

"Actually, it probably could be," Charlie said thoughtfully. "But no, that's not the depth of understanding I'm hoping for at this point. At this point, I just want more data."

"Can you wait a few minutes for me?" Don asked, and Charlie nodded. Don headed for the house, clapping Charlie on the shoulder as he passed. "Let me make a couple of calls. I'm gonna get you some data."