“He mentioned to me that what was going on at Babbage Town was worth countries going to war for. It can’t be just numbers.”

“I’m scared, Sean. Len Rivest was a very capable man. The fact that someone could kill him, like that, in his own house with security all around.” She shuddered and fell back in her chair.

She looked so miserable that Sean rose and put an arm around her shoulders to steady her. “It’ll be okay, Alicia.”

“Don’t patronize me! I’m terrified about Viggie. She could be in danger too.”

“Why?” he asked.

“You tell me. You’re the expert in this sort of thing.”

“Does the girl know her father’s not coming back?”

Alicia looked uncomfortable. “I’m trying to lay the groundwork to tell her, but it hasn’t been easy.”

“If you’re really concerned about her, then I’d get her out of Babbage Town.”

“I can’t do that.”

“I thought Viggie’s welfare was your top priority?”

“Viggie’s happy here. I can’t just uproot her and take the girl someplace she’s never been. It could destroy her.”

“I’ll admit it’s not much of a choice.”

“I have another option,” Alicia said suddenly, gripping his hand. “We stay and you help keep Viggie safe.”

“I’ve already got a job.” I’ve actually got two jobs now, Sean mentally corrected.

“She’s a child. She needs help. Are you just going to sit there and refuse to help a vulnerable little girl who just lost her father?”

Sean started to say something and then stopped. Finally, he sighed. “I guess I could keep an eye on her.”

Tears again trickled down Alicia’s cheeks. “Thank you.”

“I guess now that I’m her unofficial bodyguard I should actually meet the young lady.”

Alicia composed herself and rose. “She’s just finished doing some factoring exercises for me.”

“What?”

“Viggie has the ability to factor large numbers in her head. Not so large as to make my work obsolete, but there could be something lurking in the recesses of her mind that provides the key to unlocking the shortcut I’ve been looking for.”

“And the vulnerable little girl brings the world as we know it to a screeching halt?”

Alicia smiled. “Well, it’s said that the meek shall inherit the earth.”

CHAPTER 30

SEAN HAD EXPECTED TO FIND a shy, quiet type in Viggie Turing; however, the girl was full of energy, and her wide, blue eyes seemed to capture every movement around her. She wore a bright red shirt, Capri pants and was barefoot. After being introduced by Alicia, Viggie immediately took Sean’s hand and led him over to the piano.

“Sit.”

He sat.

“You play?” she asked, staring at him with a pair of eyes that were uncomfortably intense.

“Bass guitar. Only four strings, not so complicated. And when you’re losing millions of brain cells every day like I am that’s a good thing.”

She didn’t bother to acknowledge his little joke. Viggie sat down and played a tune that he’d never heard before.

“Okay, you stumped me,” he said. “Who is it?”

Alicia supplied the answer. “‘Vigenère Turing.’ It’s an original composition.”

Sean stared at the girl, impressed.

“You like it?” she asked simply.

He nodded. “You’re a very gifted musician.”

She smiled, and Sean could finally see the eleven-year-old girl inside, for it was a shy, eager-to-please sort of expression. And this scared him. It might make her trust people she shouldn’t. Spies here, Rivest had said.

“Viggie, do you-”

She started playing another song. When she finished, Viggie got up and walked over to a chair at the kitchen table and stared out the window. As Sean watched, her wide, dancing eyes retreated to slits.

Sean rose. “Viggie?”

Sean looked over at Alicia, who was motioning him to join her on the couch.

Speaking quietly she said, “She sort of withdraws into a little world of her own. If we wait she’ll come around.”

“Has she been seen by experts? Is she on medication?”

“I don’t know about the experts, but she’s not on medication. Now that I’m her guardian I’m going to look into it right away.”

“What do you know about Viggie’s mom?”

“Monk said they were divorced, years ago. He had full custody.”

“That’s what Rivest said. But you know, Alicia, if Viggie’s mother shows up a court will likely grant her custody unless she’s in prison or otherwise incapable of taking care of her daughter.”

“But Monk appointed me guardian.”

“That doesn’t matter when a parent is involved.”

“I’m not going to worry about that until it happens.”

“18,313 and 22,307.”

They turned to look at Viggie, who was now staring at them.

“Those are the prime factors of 408,508,091,” the girl explained. “Aren’t they?”

Alicia nodded. “That’s right. If you multiply 18,313 and 22,307 you get 408,508,091.”

Viggie clapped her hands together and giggled.

“But I just gave you that number barely an hour ago. How did you come up with them so fast?” Alicia asked.

“I saw them, in my head.”

Alicia said eagerly, “Were they lined up? Were you doing math in your head again?”

“No. It just popped into my mind. I didn’t have to do math.”

“At least not any math of which mere mortals are aware,” Alicia said thoughtfully. “Viggie, I think Mr. Sean wanted to ask you something.”

Viggie looked at him expectantly.

“Well, I just wanted you to know that I’ll be coming to see you. Would that be okay?”

Viggie looked at Alicia, who nodded.

“I guess so,” Viggie said. “But I should really check with Monk.”

“You call your dad by his first name?”

“He calls me by my first name. Isn’t that what people do?”

“I guess it is. I haven’t met your dad, but he sounds like a really cool guy.”

“He is. He played in a rock band in college.” Viggie looked out the window again and Sean was afraid she was about to lapse into one of her “funks,” but she merely said, “I wish he’d come home soon. There are lots of things I have to tell him.”

“Like what?” Sean asked, perhaps a little too quickly.

Viggie immediately rose and started playing the piano again, louder and louder.

When she momentarily stopped, Sean said, “Viggie, when was the last time you saw you dad?” This query only caused her to play even more fiercely.

“Viggie!” Sean said, but Alicia was already pulling him toward the front door as Viggie smashed her fists down on the keyboard and raced out of the room. A few seconds later they heard a door slam. An instant later the woman Sean had seen sleeping on the couch the night before entered the room.

Alicia said, “I’ll be back in a few minutes to check on her, Mrs. Graham.” Alicia led Sean from the house.

“Okay, I see your problem with Viggie,” he said, scratching his head.

“I think she knows, deep down, that there’s something wrong with her father. Anytime anyone starts nibbling around that subject she just shuts down.”

He caught sight of Viggie staring at them from her bedroom window and then, like a thought he’d lost in his head, she was gone.

Sean turned to Alicia. “Those numbers she told you. Couldn’t she have figured it out on a calculator?”

“Yes, but it would have taken her about a full day to do it. 18,313 is the 2,000th prime number, meaning she would have to have gone through all those that preceded it to see if it divided into 408,508,091 without leaving a remainder. She just saw it in her head, like she said.”

“And tell me why this is so important?”

“Sean-”

“Damn it, Alicia, people are dying here. I’ve agreed to protect Viggie because you think she’s in danger. The least you can do is start telling me why.”

“All right. The world runs on information sent electronically. How to move it from A to B safely is the key to civilization. Using your credit card to buy things, getting cash from an ATM, sending an e-mail, paying bills or purchasing things online. Encryption these days is strictly about numbers and their length. The strongest system is based on asymmetric public key cryptography. It’s the only thing that makes electronic transmissions, from government to commercial to private citizens safe and thus viable.”