“Well, one was bought in London; one was bought in Wellington, New Zealand; one was bought in Saint Petersburg, Russia. The last was from Punta Arenas, Chile.”

“What am I not seeing in those four locations?”

“Wellington and Punta Arenas share a distinction as major jumping-off points for Antarctica.”

“Antarctica. Why … never mind. I had another text exchange with Lear. Here’s the number.” She read it off to him. “Why doesn’t Lear just block the number?”

“Excellent question,” Stern said approvingly. “Arrogance? Or, more likely, he’s deliberately leaving breadcrumbs. Either a false trail, or …”

“Or what?”

“Or a trail meant for the right person to follow.”

A game? Was she supposed to believe that Lear was playing a game with her?

In the coffee shop, Caligula was standing up. He put on his hat, straightened it carefully, and looked directly at Sadie, who returned his gaze evenly. Then he tugged at the front brim in a slight but unmistakable acknowledgment of her, and faded from view as he moved away.

Stern caught the gesture and said, “And you’re sure we shouldn’t question him?”

“He’s tight with Lear. He’s Lear’s attack dog. And I may need him.”

“What are you planning?”

Plath shrugged. “Lear’s orders. He still wants us to wipe out all AFGC data on nanotechnology. And soon.”

Stern took a long pause at that. He searched her face, looking for something to reassure himself. But reassurance did not come, and now he was wary. “Have you told Lear about the practical objections to such a harebrained scheme?”

“No,” Plath said. “Not yet.”

She hesitated, unsure if she should go forward. Stern was an experienced interrogator—he knew when just to wait.

“It’s just …,” Plath began. “It’s just, well, I was thinking … a bomb of some kind?”

“A bomb? Are we back to that?” He shook his head slowly without shifting his gaze from her. When she said nothing, he said, “Sadie, please listen to me. I’ve been to war. I was in Iraq, and before that I was in Somalia. When you’re in it, when you’re scared and when you’re mad and you want revenge, maybe, you find yourself thinking about doing things no human being should do. You think about crossing the line.”

“Where’s this line, Mr. Stern? The Armstrongs killed my father and brother. They basically killed the president of the United States, even if that’s not what they intended. Burnofsky was trying to unleash self-replicating nanobots that could kill every living thing on the planet. So where’s the line?”

Stern put down his coffee, carefully crumpled the paper from his sandwich, and set it aside. He wiped his hands with a napkin. Then, with a clean forefinger, he pointed at Plath’s forehead. “In there.” Then he pointed at her heart. “In there. That’s where the line is.”

It was not easy to meet his worried, penetrating eyes.

“Sadie, you need to ask yourself: Is this you? Are you really, truly a person planning what would look like a terrorist attack in Midtown Manhattan?”

Finally she couldn’t take it and turned away. “No, of course not. But get me everything you can, okay? Everything you feel okay about giving me. I still need to find a way.…”

He wasn’t buying it. And for a moment she was afraid he might just walk away. Then, with a pained expression, an expression of loss, he nodded his head.

ELEVEN

Saks would not release the store surveillance video. But Mr. Stern had excellent connections throughout security companies in New York. An underpaid guard, when offered ten thousand dollars in untraceable cash, decided he could in fact arrange for the video file to make its way to Mr. Stern.

He in turn passed it along to Plath. Who watched it for the third time with Keats, Wilkes, and Anya. Billy had not been asked to be present, but he was, anyway.

They decided that there was no need for Vincent to be subjected to it in his condition.

His condition. Fragile, that was his condition. Borderline nuts, still. High-functioning unbalanced.

“Jin lost his shit,” Wilkes said on a second viewing. “Look. That’s when it starts. He’s fondling a pair of pants. Then that’s him texting.”

“ ‘Two new biots,’ ” Plath said dully.

“The text was sent three minutes later,” Noah pointed out. He had compared the video time code to the time signature on Plath’s phone.

They watched the second part of the tape. Nijinsky hurling himself down the escalator. There was no sound. The video was decent quality, but the angle was poor. They were seeing him from behind.

“Jesus Christ, how many times do we have to watch this?” Wilkes cried suddenly. She stormed off to the kitchen. Then came back with a bag of chips.

“ ‘Two new biots,’ ” Keats said. “But he was against getting anymore.”

The third segment of tape showed a distraught Nijinsky, face-on this time, kneeling, feeding his scarf into the escalator.

It went on for way too long. Nijinsky dead. People milling around helplessly. Store employees rushing over with scissors, trying to get at the scarf and cut him loose. Failing, because it was too tight, too tangled.

Eventually a security guard. Then, at last, far too late, the paramedics.

“He went crazy,” Anya said. “It was deliberate. He was looking at clothing and then he was killing himself. Madness.”