A sharp ping sounded from the device’s internal speaker.

Then, my own phone—the one with the battery supposedly removed—began to vibrate in my lap.

The phone was cold, but it pulsed against my palm.

I stared at the empty battery compartment on the passenger seat.

The screen glowed white, displaying a single, spinning gears icon.

“How is that possible?” Mara whispered.

Her knuckles were white on the steering wheel.

“An embedded reserve,” I said. “A secondary lithium cell soldered directly to the logic board.”

My mother had designed the secure communications protocols for the defense department.

Of course she had modified my personal devices before she gave them to me.

“Throw it out,” Mara said.

I rolled down the passenger window.

Cold rain lashed my face as I flung the metal and glass casing into the dark.

It bounced once on the asphalt of the New Jersey Turnpike and vanished under the wheels of a passing semi-truck.

But the portable monitor in my pocket kept blinking.

The green light was steady, mocking me.

“We need to get off this highway,” I said.