Eli was whatever the opposite of athletic was; he was tall and skinny but not like in a fit way. At lunch every day, he sat with a group of guys who were all into video games that Marwan had no time for, or maybe just no interest in. He and Eli had had an early class together last year, and Eli always came in looking like he’d stayed up too late—no doubt playing dumb games with remote competitors—and his grades notoriously suffered. He was a going-nowhere kind of guy who Marwan stayed away from without having to work very hard. They were on paths to entirely different destinations, so those paths never crossed.

His and Eden’s paths had crossed enough times over the years that he’d felt physically ill when he heard about her father’s accident. The school had really rallied around her and her mom—delivering meals and raising money—and flowers had appeared … then died at the intersection where it had happened. It was the reason Marwan had started wearing a helmet. But he and Eden had never been actual friends. He had the sense she was a bit of an outsider like he was, but somehow their outside spaces didn’t overlap.

The cube pulsed new letters.

“What now?” Marwan asked, hand on the doorknob.

Eli smiled. “It says, ‘Do not shake the device.’ ”

“This is freaking me out,” Eden said.

“It’s obviously a game or something,” Eli said.

A new message flashed. Marwan let go of the doorknob and went to look for himself. Two stacked sentences:

DO NOT TELL ANYONE ABOUT THE DEVICE.

DO NOT LEAVE THE DEVICE UNATTENDED.

It went dark again.

“Well, if it’s a game,” Marwan said, “I’m not playing.”

“You’re not even a little intrigued?” Eli asked.

“Nope!”

“Just hold up a second,” Eli said. “I’ll message McKay.” He typed into his phone.

Marwan scrolled through headlines while he waited—only because he liked Mr. M, who’d actually turned him onto Disgraceland, a podcast about notorious rock and roll mysteries.

The top headline was another mass shooting.

California. White guy. Non-Muslim.

Always a relief.

Just last week, Marwan had relistened to a podcast about anti-Muslim crimes in the days after 9/11, and it made his stomach sour. His family wasn’t really religious—his sisters wouldn’t wear headscarves like Numdal did when they got older; his mother didn’t—but they were still culturally Muslim. So people made crazy assumptions about their worldview—or at least people like Christos did.

“This is weird,” Eli said. “The original message I got about the urgent matter is gone.”

Marwan opened the app; his message was gone, too. The girls also reached for their phones.

Eli’s phone dinged. He looked at it and said, “Mister M says there must be some mistake because he’s out sick today and didn’t send the message.”