Leo had already tried eight.

The phone’s screen went white, then black, then a single line of text appeared:

A voice, Ethan’s, but frayed, like a rope about to snap:

A tiny LED on the phone’s side blinked orange. A microSD card popped out, landing on the bed like a seed. Leo snatched it. The phone began to hiss, then smoke—a controlled chemical meltdown of its memory chips.

The device was a prototype—a shadow variant of the commercial model, codenamed Nightingale . Ethan, a senior security architect at Samsung’s R&D lab in Suwon, had brought it home for “real-world penetration testing.” The phone looked ordinary, but its core was a labyrinth of encrypted partitions, biometric misdirection, and a kill switch that would wipe everything after ten failed attempts.