Just making plans, Watt answered vaguely, though he never could hide anything from Nadia for very long. And she was right.

Even while he’d been in that math session, a part of his mind—a part that was dangerously close to the whole—had been thinking about Leda, alternating between fantasies of her demise and fantasies of a decidedly different nature. He didn’t understand his fixation with her. How could he resent her, want to make her to pay for everything she’d done, and yet still want her as much as he did?

He wished he could be more like Nadia. More rational, less reckless.

Speak of the devil, Nadia flashed before his eyes. Watt looked up, and was struck speechless at the sight of Leda herself, lounging casually against a brick wall at the edge of his school’s tech-net, seven hundred floors below her own. She was wearing black yoga pants that left little to the imagination, and her face was glowing from exertion. Her hair was swept up into a loose knot, though a few damp curls escaped at her ears.

“Watt. There you are,” she greeted him, with a note of possessiveness that simultaneously thrilled him and pissed him off. He wanted to kiss her, roughly, right there. But he didn’t.

“Leda,” he said slowly, to cover his strange mix of feelings. “To what do I owe the pleasure?”

Next to him he felt Cynthia tense at the name, glancing back and forth between them. He knew what she was thinking: so this was the infamous Leda, the girl who knew far too many of Watt’s secrets.

“I need to talk to you about something. In private.” Leda’s eyes darted to Cynthia. “Sorry, I don’t think we’ve met. I’m Leda Cole. Cynthia, right?” she asked, holding out a hand. Cynthia didn’t take it.

How did Leda even know who Cynthia was? He must have mentioned her, Watt thought—or else Leda had been trolling through his page on the feeds. He found the notion strangely pleasing.

“Hi, Leda,” Cynthia said, without moving forward. It was clear from her tone what she thought of the other girl. After a moment, Leda lowered her outstretched hand and turned to Watt.

“Watt? Let’s go,” she commanded, and started off, clearly assuming he would follow.

Watt looked back at Cynthia. “Sorry, I have to—”

“Whatever, the queen bitch summons,” Cynthia said tartly, too low for Leda to overhear. “Go ahead.”

Watt didn’t hesitate. Cynthia would forgive him later, but Leda never would. He hurried to catch up with her. “You didn’t need to make that scene,” he said, though for some reason he’d found it a little entertaining. Maybe he was getting too accustomed to being with Leda Cole.

“Sorry if I made things difficult with your girlfriend,” Leda said briskly.

“I’ve told you before, she’s not my girlfriend.”

“I’ve told you before, I don’t care.” She didn’t even glance his way as she turned onto his street. Watt was a little surprised that she wanted to go to his place tonight, and even more surprised that she knew her way around down here.

“Look, if you wanted me to come over, you could have just messaged me,” he said, his mind already racing ahead to what his parents would say when they walked in together. Though they’d met Leda before; they thought she was a classmate, after all.

Leda laughed. “I’m not here for that,” she said, and he loved the way she said “that,” as if she wanted to be dismissive of the notion but couldn’t quite manage it.

“There’s someone I need you to look into,” Leda went on. “I keep meaning to ask you about her, but, you know …” She broke off awkwardly.

“But I keep distracting you.” He grinned at her discomposure.

“Don’t flatter yourself.”

They stepped up to his front door. Watt hesitated and glanced over at Leda. “Could you just tell my parents that you’re here for a school project, and—”

“Relax, Watt. This isn’t my first rodeo.”

“I don’t even know what that means,” he replied as he opened the front door. “What the hell is a rodeo?”

Leda shrugged. “It’s an old saying,” she said dismissively, and followed him down the hallway, her expression transforming from exasperated sarcasm into a brilliant smile. “Mrs. Bakradi!” she exclaimed, going to give Watt’s mom a hug. “How are you? I’ve been meaning to bring this over for Zahra. I found it when I was cleaning out some of my old things.” To Watt’s astonishment, Leda reached into her purse and produced a tiny horse figurine. She pushed a button and the horse began running across the floor.

Damn, she was good, he thought with grudging respect.

When they were finally in Watt’s bedroom with the door shut, Watt stared at Leda. She’d already claimed a seat on his bed, crossing her legs beneath her with proprietary ease. “How did you know that Zahra’s in a horse phase?” he asked suspiciously.

“Your mom told me the last time I was here.” Leda rolled her eyes. “Seriously, Watt, that quant of yours has made you unforgivably lazy. Do you ever listen to people?”

“I listen to you,” he replied, caught off guard by the insight.

“I don’t think so,” Leda said lightly. “Is Nadia on?” For a moment Watt thought he was dreaming; it was still surreal hearing anyone talk about Nadia.

“I’m always on,” Nadia replied, projecting from the speakers. She sounded slightly offended.

Leda nodded as if unsurprised. “Nadia,” she said, with a respectful tone she never used with Watt, “would you please research someone for me? Her name is Calliope Brown. She’s around our age.”

“Searching now,” Nadia replied.

Watt felt increasingly annoyed. You’re making it too easy on her.

She asked nicely. Unlike you.

“Just what are we looking for, exactly?” Watt sank into his desk chair and stretched his arms overhead, trying not to think of how close Leda was, the fact that she was so casually sitting there on his bedsheets.

“I’m not sure,” Leda admitted. “But something is off about this girl, I know it.”

“So we’re basing this on a hunch of yours?”

“Laugh all you want, but my hunches are spot-on. After all, I had a hunch that there was something off about you, and I was right, wasn’t I?”

Watt had nothing to say to that.

Leda leaned forward as Nadia’s search results populated the monitor. There was a Calliope Brown registered in the Tower, on floor 473—an older woman with a narrow smile. “No, that’s not her,” Leda said, disappointed.

Watt frowned. “Nadia, can you widen the search to the United States?” They scrolled through dozens of faces, then expanded the search internationally, but Leda just shook her head impatiently at every image that appeared.

“She’s staying at the Nuage! Can we find her that way?” Leda impatiently yanked out her ponytail to redo it.

“I’ll show you the cams at high-speed, pulling out the faces. Tell me which one she is,” Nadia offered, using snapshots of the video feed to create an instant database of all the guests. Watt could feel Nadia getting into the search a little, despite herself. There was nothing she loved more than a good puzzle.

After a few minutes of scrolling, Leda leapt off the bed, pointing to a figure in the top right. “There, you see! That’s her!”

“Nadia, can you grab her retinal scans?” Watt asked. Moments later Nadia had pulled up the information. The girl’s retinas were registered to Haroi Haniko, a woman from Kyoto who’d died seven months ago.

“Okay. She’s got a stolen retina pattern,” Leda said, clearly stunned. “She must be a criminal, right?”

Now even Watt was getting curious. “Nadia, what about facial-reg? Full international scope.” She could change her eyeballs, he thought logically, but it was much harder to drastically change her face.

The screen came up blank. “No matches.”

“Try again,” Leda asked, but Watt shook his head.

“Leda, that search included every government—national, state, province, municipal—in the entire world. If this girl existed, we would have found her.”