“What did you say?” asked Lee.
“The Fibonacci sequence. Each succeeding number is arrived at by adding the two previous numbers. One, one, two, three, five, eight—”
“Wait a minute—start over, would you?”
“One, one, two, three, five, eight . . . the golden mean.”
“The golden what?” said Jimmy.
“The golden ratio,” Barry said in a singsong voice.
“The higher you go in the Fibonacci sequence, the more closely the ratio between two successive numbers in the sequence approximates phi.”
“What’s phi?” asked Jimmy.
Barry rocked gently, staring into space as he recited. “Phi is an important mathematical constant known as the golden mean. Specifically it is approximately 1.61803.” He pointed to the pictures of the designs on the girls’ torsos. “In fact, these are Fibonacci designs seen in Nature.”
“Oh, my god,” said Lee. “What if that’s
it
?” He looked up at Barry, still clutching his stuffed panda, his face expressionless. “Barry, you’re a genius!”
“No hugging,” said Barry.
Lee looked at Jimmy, who said, “He’s afraid you’re going to hug him. He doesn’t like to be touched.”
“Barry, I promise I will never
, ever
hug you,” said Lee. “But I could kiss you!”
Barry frowned. “No kissing.”
Jimmy and Lee looked at each other and burst out laughing. As he watched them, Barry’s face broke into an awkward smile. His muscles appeared unaccustomed to the expression—his smile was like cracks appearing in a concrete floor.
He hugged his stuffed panda. “I’m a genius.”
“You sure are, Barry,” said Lee. “You’re a goddamn genius.”
“Goddamn genius,” said Barry, with a little giggle. “I’m a goddamn genius.”
“So if Barry’s right,” Jimmy said, “then next time the UNSUB will—”
“He’ll cut off three fingers,” Lee said.
He stared out the window. Somewhere, out beyond the friendly bustle of pedestrians, street vendors and the traffic of Chinatown, a killer lurked, calmly calculating the mathematics of death.
C
HAPTER
F
IFTY-NINE
M
orris Epstein was an absentminded professor straight out of central casting. A nervous little mole of a man with tobacco-stained fingers, he trailed a cloud of stale cigarette smoke behind him. His teeth were as gray as the wisps of hair growing around his ears, and his bald pate was as shiny as a polished apple. His prominent brown eyes appeared even larger and rounder behind a pair of black bifocals mended at the corner with duct tape. They perched lopsidedly on his short nose, which didn’t look up to the task of supporting such thick lenses. He was constantly pushing them back into place, after which he emitted a sniffling sound, as though the effort had triggered an allergic reaction.
They had interviewed a steady stream of faculty members of various colleges around town, including Yeshiva, where one of the victims was a student, but Morris Epstein was their first Columbia professor.
He sat in the chair Lee offered him and gazed around the room, gnawing on already well-chewed nails. Butts entered moments later, rumpled as usual, a packet of potato chips protruding from his jacket pocket.
“Good afternoon. I’m Detective Leonard Butts, and this is my colleague, Dr. Lee Campbell.”
“Is this about that terrible strangler?” Epstein asked. “The one who’s been killing college girls?”
“Yes, but there’s no need—” Butts began.
“Am I a suspect?” Epstein blurted out, giving his glasses a push with his index finger.
“Not at this time,” the detective replied. “We’d just like to ask you a few questions.”
Not at this time.
Why had Butts given such a qualified answer? It was a good way to scare potential suspects, but Lee couldn’t think why the detective would want to frighten this inoffensive little man.
“Very well,” Epstein said, “as long as I make it to my three o’clock lecture.”
“I’ll be sure to keep that in mind,” said Butts.
Lee noted the detective was keeping control of the interview by withholding whether or not he’d grant Epstein’s request.
“Now, then, Mr. Epstein,” Butts began.
“Actually, it’s
Dr.
Epstein,” the professor corrected him.
“
Dr.
Epstein. You’re in the math department at Columbia, right?”
“Yes. I teach undergraduate courses in trigonometry and calculus. And a graduate course in the history of mathematics. Did you know that calculus was invented by Sir Isaac Newton?”
“No, I didn’t,” said Butts. “Now—”
“A lot of people know that the Egyptians came up with the system of numbers we now use, but you’d be surprised—”
“I’m sure I would,” Butts interrupted. “If I could just ask you a few questions—”
“I’m sorry—was I rambling?” he said, repeating the glasses-pushing ritual. “I tend to do that when I’m nervous. That’s what my wife tells me, at any rate. Are you married, Detective?”
“Yeah. Now, if you—”
“Wonderful creatures, women. Of course, they’re utterly beyond comprehension, but that’s what makes them so appealing, don’t you think?”
Lee was impressed. He had seen suspects try to out-macho Butts, which never worked, out-maneuver him, which rarely did, and even try to soften him with humor and charm (he was as impervious to that as he was to Elena Krieger’s charms). But he had never seen an interviewee simply do an end run around him. It was hard not to admire Morris Epstein, even if all his chatter was the result of nerves, as he claimed.
“Look, Mr.—uh, Dr. Epstein,” Butts said, running a hand over his brow, “you got a three o’clock lecture, right?”
“That’s right.”
“And I got a case with a hole in it the size of the Lincoln Tunnel. So if you don’t mind, I’d like to ask you a few things, and then you can go teach your class.”
“I’m ready when you are.”
“We have reason to believe the person we’re looking for might be a math teacher.”
“How intriguing. May I ask why?”
“I’m sorry, but I can’t divulge the particulars of this case.”
Lee noticed that the detective’s vocabulary had taken an upswing. One effective technique of interviewing a suspect was to mirror their body language. Maybe Butts was doing the verbal equivalent, adjusting his language to fit the way the professor spoke. The stubby detective’s unsophisticated appearance and crude manners masked a keen investigative mind.
“Why not a student?” Epstein said.
“What?” said Butts.
“Why couldn’t your killer be a math student? Did you consider that?”
“We did, yeah.”
“And?”
Butts looked at Lee.
“We felt the UN—uh, the suspect—would be older,” Lee answered.
“I was wondering when you were going to speak,” Epstein said to Lee, stabbing at his glasses again. “You were about to say
UNSUB
, weren’t you? I know what that is. It’s short for
Unknown Subject
.”
Butts and Lee exchanged a glance, and Epstein smiled. “Come, now—everyone who watches television knows that term.”
“I’m glad you know your police terminology,” said Butts. “Now, then—”
“You’re that profiler, aren’t you?” Epstein said to Lee. “The one whose sister disappeared.”
“Yes.”
“Any leads on what happened to her? Why aren’t you working on that case?”
“That investigation is at a dead end,” Lee said.
“That’s terrible.”
Lee glanced at Butts, whose face was a deep shade of purple.
“All right,
Dr.
Epstein,” the detective said, “if you ask
one more question
, I will personally see to it that you miss your lecture.”
The professor shook his head ruefully. “I am so sorry,” he said meekly. “I’m doing it again—chattering because I’m nervous.”
“Okay, then,” said Butts. “What we’d like to know is if there are any members of the math department who you would consider . . . odd.”
Epstein laughed. “My dear detective, we’re talking about
mathematicians
. We’re
all
odd.”
Butts bit his lip. Lee had never seen him so frustrated in an interview.
“Let me put that another way,” he said. “Is there anyone in your department who you might—”
“Whom I might suspect of being a serial killer?” Epstein said.
Butts rolled his eyes.
“Well, that’s what you’re asking, isn’t it?” Epstein asked.
“Okay,” said Butts. “Is there anyone in your department—”
“As a matter of fact, there is,” Epstein answered in the conspiratorial tone of a parlor room gossip.
“And do you want to tell me who that might be?”
“Will I get to my lecture on time?”
“Yes, you will.”
“First, may I have a cup of coffee?”
Butts stared at him.
“My wife said she heard that police precinct coffee was horrible, and I want to see for myself. I’ve never been in a police station, you see. She’ll never forgive me if I don’t try the coffee.”
Butts sighed heavily but opened the door to go get the coffee.
Epstein called after him. “Milk and sugar, please.”
Butts left the interrogation room and returned in less than a minute. He handed Epstein a paper cup of black coffee.
In response to his frown, Butts said, “We’re all out of cream.”
Epstein took a sip and shuddered. “She was right—it’s wretched. Not as bad as the coffee in the math department, mind you, but dreadful.”
Lee suspected that the coffee contained a fair amount of Butts’s DNA, in the form of saliva.
“Now, then,” the detective said, sitting across from the professor, “you were saying?”
“Ah, yes—the serial killer. It’s terrible, really, what he does to those young girls.”
“So this colleague of yours,” Butts prompted. “What’s odd about him?”
Epstein sipped his coffee thoughtfully. “He’s—
dif-ferent
from the rest of us.”
“How so?”
“Well, Detective, I imagine there are certain types of people who become police officers. I mean, there’s bound to be a range of personality types, but they would tend to have certain traits in common, right?”
“Such as?”
“Men of action who like authority and power, who are courageous, maybe athletic, decisive—that kind of thing.”
“Okay—go on.”
“It’s the same in a math department of a large university. We all tend to be bookish, rather
un
athletic, highly intelligent, somewhat socially challenged and so on. In other words, classic nerds. Of course, there’s some variation—Paul Dumont, who also teaches physics, is a rock climber. Physicists tend to be more athletic, for some reason. But he’s still a nerd.”
“So this guy you’re thinkin’ of—”
“He’s odd in a different way. He’s . . . how to say it?”
Butts leaned back in his chair and crossed his arms. “Take your time, Doc.”
“Well, the rest of us have a kind of
innocence
, if you will. Our IQs might be in the stratosphere, but there’s a curious naïveté about us, if you get my drift?”
“I know what you mean,” Lee said, thinking of Jimmy Chen’s brother, Barry.
“Well,” said Epstein. “This colleague of mine . . . I hate to say it, but he’s—sadistic.”
“How so?” asked Butts.
Epstein shook himself as a dog might shake water from its coat. “There was—an incident. It happened quite a while ago, but I’ve never forgotten it.”
“What’s his name?” said Butts.
Professor Epstein looked at Lee beseechingly. “I feel somewhat uncomfortable about being placed in this position. What if I’m wrong, and you arrest him?”
“I understand your concerns, Dr. Epstein,” Lee reassured him. “At this time we’re simply looking for potential suspects. We would never arrest someone without sufficient evidence pointing to his guilt.”
Epstein sighed and nibbled on his index finger. “All right. His name is Moran—Professor Edmund Moran.”
Butts scribbled down the name. “So this incident you mentioned—when was it?”
“It was maybe five years ago.”
“What happened?”
Epstein gave his glasses a mighty shove. “It was about this time of year—around the holidays, you know. Several members of the math faculty were up for tenure—including Professor Moran.”
“And yourself?” said Butts.
“I already had tenure,” he replied, without attempting to hide the satisfaction in his voice.
“Go on,” said Lee.
“Well, one of the other professors up for tenure has a withered leg—polio as a child, you know, just before the vaccine was widely available.”
“What’s his name?”
“Nathan Dryansky. His parents were Holocaust survivors.”
Lee glanced at Butts. Though the detective rarely spoke of it, he knew that Butts had lost family members in the camps.
“Go on,” Butts said evenly.
“Well, I happened to be on my way to a class on the second floor just as Professors Dryansky and Moran were coming down the stairs. They’re marble and quite slippery, you know,” he said, looking at Lee, who nodded.
“Dr. Moran was behind Professor Dryansky, and as I passed them, I heard Dryansky cry out. I turned around to see him tumble down half a flight of stairs. Moran was closer to him than I was, and I expected him to run down and help Dryansky to his feet, but he just stood there grinning. So I dashed down and helped him get up. He wasn’t badly injured, but he was quite bruised and terribly embarrassed. All the while, Dr. Moran just stood there with the strangest smile on his face. It was quite horrible, really. Not only that, but I had the impression . . . well, it’s only speculation, of course—” He looked at the other two imploringly.
“Go ahead,” Butts said.
Epstein gave his glasses a halfhearted push and stared at his hands. “I had the feeling Dr. Moran might have pushed him.”
Lee and Butts exchanged a glance.
“Thank you, Dr. Epstein,” Butts said.
“Did Moran get tenure?” Lee asked.
“Not that year. He did the next, however. He wrote a rather influential paper on the Fibonacci sequence in nature as seen in the chambered nautilus.”
“Did you say the Fibonacci sequence?” Butts asked, his voice tight with excitement.
“Yes. You know of it?”
“We know something about it,” Lee replied.
“I must say, I’m impressed,” Epstein said. “Uh, am I free to go?”