My hands were cold, and I tucked them into the pockets of my cardigan to keep them from shaking.

“I’m running a cross-reference query now,” she said.

The laptop fan grew louder, a high-pitched hum that filled the space between us.

We waited in silence.

On the wall, a battery-operated clock ticked with a heavy, rhythmic click.

“Here,” Sarah said, her finger tapping the glass screen. “Look at this cluster.”

A block of data highlighted itself in bright yellow.

“On October twelfth, two days before Blake saw those texts, there was a manual override on the internal cellular relay,” she said.

“What does an override mean?” I asked.

“It means someone bypassed the automated security logs to input external data directly into the server’s outgoing queue,” she said.

She scrolled down further, her eyes scanning the hex codes.

“They didn’t just send messages,” she whispered. “They spoofed the header info.”

“Explain that to me like I’m not a coder, Sarah.”

“They took a draft message created inside the building and altered the packet sender field,” she said. “They made the server believe the message originated from your cell phone carrier’s tower in Queens.”