“Thanks, Oscar,” said Ruby, picking one out. She held it up and paused. “Are these…?”

“Lemon-coconut-shortbread cookies with white chocolate centers,” Oscar said, his ears turning pink. “Yes. Yes, they are.”

Ruby gawked at him. “That’s … my mom makes … these are my favorite!”

“Yeah, I know.” Oscar cleared his throat awkwardly and held the tin toward Nova. “I, uh, called your mom for the recipe.”

With little appetite, Nova waved away the cookies, while Adrian took three. Ruby continued to stare at Oscar, the forgotten cookie halfway to her mouth. He didn’t return the look. Instead, he slammed the lid back onto the tin and nodded at Adrian, as if eager to move on from what might have been the most blatant confession of adoration that Nova had ever witnessed. “Okay, then. Great. Let’s do this. Where do we start?”

Adrian shoved the first cookie in his mouth and approached a freestanding whiteboard. Grabbing one side of it, he pushed it away from the wall and swiveled it around so they could see the back side.

Nova’s stomach plummeted.

It was a corkboard plastered with notes and diagrams and evidence. A map of Gatlon City covered nearly the entire board, with locations circled where Nightmare had been seen. The buildings where she and the Sentinel had faced off during the parade. Cosmopolis Park with its abandoned fun house. Renegade Headquarters. Various subway tunnel entrances. The Cloven Cross Library was highlighted, too, with notes about the Detonator and the Librarian. And the cathedral, beside which was tacked a recent newspaper article about the capture of Ace Anarchy.

There was a grainy picture of Nightmare tossing the Puppeteer out of his hot-air balloon. A red circle was drawn around her face, with a line connecting it to HQ, and another line drawn to Cosmopolis. Beside the line, in bold letters, Adrian had written: FACE MASK?

Another line connected headquarters to Adrian’s house, along with the scrawled words: VITALITY CHARM???

Another line from the parade to the library. WEAPONRY? And in parentheses—(sharpshooter).

Another line, from HQ to the cathedral. ACE ANARCHY HELMET?

To the side of the map was a series of messy notes and asides.

How was she immune to Agent N and Max? Vitality Charm?? But how did she know about it? How did she GET it?

How did she get the helmet out of the chromium box?

How did she know the helmet wasn’t destroyed? / Where it was kept?

Access to Agent N?

Agent N bombs—Fatalia’s mist-missiles!

Each of the questions had a line drawn back to Renegade Headquarters.

Nova gulped, hard. Her skin prickled and her legs twitched with the urge to bolt for the door. It felt like a setup, but no one was looking at her.

Ruby stood, brushing cookie crumbs from her fingers, and approached the board. “Okay,” she murmured, rocking back on her heels. “What does it all mean?”

Adrian’s expression was dark as he inspected the map, too, as if waiting for a new clue to jump out at him and piece it all together. But he had already pieced together enough.

Nova knew what he was going to say before he said it.

Her heart hammered, waiting for the words.

“I do have a theory,” he started, speaking slowly, his brow drawn.

“We’re listening,” said Oscar. In the same moment, a dozen of Danna’s butterflies lifted off Adrian’s desk and twirled around the board, before settling on its top.

“For starters,” said Adrian, “Nightmare knows too much—about Agent N and Max, maybe even the Vitality Charm—”

“Pause,” said Ruby, holding a hand toward him. “What is the Vitality Charm?”

Adrian cleared his throat. “It’s…” He hesitated again, and Nova could see his thoughts forming as he tried to reason through how best to explain to her this incredible object he’d discovered. “It’s an old charm that was found in the artifacts departments. Anyone who’s wearing it will be protected from illness, poisons, venom, and even … something like Agent N. Or Max.”

“You’re kidding,” said Oscar, cocking his head to one side. “Why haven’t we heard about this before?”

“I wanted to tell you, but my dads asked me to keep it a secret until they knew more about the charm and its limitations. They were worried its existence might interfere with the launch of Agent N. And now it’s missing.”

“Missing?” asked Ruby.

“Simon had it last. He was able to visit Max with it. But we haven’t seen it since before Nightmare broke into headquarters.”

“So Nightmare stole this thing from the Dread Warden?” said Oscar. “What? Did she, like, pickpocket him?”

Adrian tapped his marker against his palm. “Pops said he left it here at the house, but I don’t know. Maybe he forgot, and it was actually at headquarters. Because, listen, all of these things”—he swirled the marker around the board—“were at HQ. The helmet, the Silver Spear, and even those bombs she had. The Vitality Charm, if she did have it … maybe it was at headquarters, too. And oh, the mask!” He pointed at a grainy photo of Nightmare, showing the metal mask across the lower half of her face. “Frostbite’s team said she was wearing it last night and it was identical to the one she used to wear. I’m convinced that it is the mask she used to wear.”

Nova sank deeper into the sofa.

“So?” said Oscar.

“So,” said Adrian, “her mask was found in the debris at the Cosmopolis fun house. I saw it myself, after the explosion went off that was supposed to have killed her. I talked to Magpie, and she swears it was collected by the cleanup crew and handed over to the artifacts department, but they have no record of it. And Stingray’s statement says that Nightmare was in full costume when she attacked him in the security room, even though that was before she went to the vault.” He pointed to a pieced-together timeline of the HQ break-in along the bottom of the board, where it was indicated that Nightmare had used Stingray’s wristband to access the vault’s door.

“Which brings up another point,” continued Adrian. “Nightmare went out of her way to make sure she hit the security room and disabled all of the surveillance cameras before she went after the helmet. But she wears a mask! Why would she care if she was caught on video footage unless she worried that someone might recognize her.”

Nova raised a finger, glad that this, at least, she could make a decent rebuttal against. “If she went into the vault while the cameras were still on, it would have triggered the security team to come after her right away. She would have had to disable the cameras to give herself time to complete the theft before anyone realized what she was doing.”

Adrian considered this, then gave a half shrug. “Maybe. But there’s also Agent N.” He tapped the large board enthusiastically. “I got the report a few hours ago. Those devices they found in the lobby were definitely Fatalia’s mist-missiles—gas bombs that were stored in the vault—and Nightmare had definitely reengineered them to release a gaseous form of Agent N, which not only means she had the bombs before she broke in, maybe even weeks before, but she also had a supply of Agent N, which is kept in a secure storeroom behind the laboratories. Either Nightmare broke into that storeroom before her attack on HQ the other night, or she was able to get her hands on Agent N some other way.”

“But who else has access to it?” said Ruby, stealing another cookie from the tin.

Adrian fixed her with a serious look. “We do.”

“Whoa,” muttered Oscar. “You totally just gave me chills. But what does that mean exactly?”

“We have access to Agent N,” said Adrian. “All patrol units. Everyone who’s been in training the past few weeks. And the Council, obviously. And everyone who works in the labs.”

Oscar rolled the chair forward, pushing off with the balls of his feet. “Go on. I feel like this is about to get really good.”

Adrian scratched the back of his head. “It might seem far-fetched, but I have this theory, and it answers so many questions. How she knew about Agent N, and how she was able to steal some before we’ve even announced it. How she had access to the vault. How she knew about Max, and the team that would be on security detail that night, and the helmet, and all of it. I think…” He paused to take in a deep breath. “I think Nightmare has been posing as a Renegade. I think she’s a spy.”

Nova flinched. She squeezed her eyes shut, only for a second. There it was. The remark that would unravel it all.

Still, she forced a mask of surprise onto her face as her fingertips dug into her thighs. “A spy?” she said, daring to speak, and hoping that the slight quiver in her voice added to her apparent disbelief. “In the Renegades?”

As one, the hundreds of butterflies surrounding them opened their wings in perfect unison, and then closed them again and went back to stillness.

It was as much a confirmation as if Danna had been sitting on the couch between Nova and Ruby, ready to jut her accusatory finger in Nova’s direction.

“Yikes,” muttered Oscar. “That was weird.”

“Danna,” said Adrian. “I’m right? Do you know who it is? Or how we can find her?”

And though Nova had been sure that Danna wasn’t supposed to be able to hear, let alone comprehend spoken language, in swarm mode, they must have understood well enough. As one, the butterflies lifted into the air, circled once beneath the ceiling, then came to settle.

Directly on Nova.

She squeaked and stiffened as the butterflies and their dainty feet perched on her shoulders, her hair, her arms and knees and toes. Those who couldn’t fit on her body surrounded her, taking up residence on the cushions and the back of the couch.

Nova held her breath, suddenly too afraid to move. She wasn’t the only one who had gone motionless. Adrian was gawking at her, his mouth hanging open.

The butterflies lingered only a moment before they took to the air again and found their way to the distant corners of the room.