At first, it was just a faint sound — a low, resonant hum, almost like the vibration of distant machinery.

But the hum wasn’t coming from the walls or the power grid.

It was coming from inside the case.

Evelyn froze as the pulse quickened, shifting in rhythm, as if matching her heartbeat. Hale’s grip on the handle tightened, but the metal was warming fast beneath his hand.

He hissed and dropped it onto the floor. The case struck the concrete with a metallic thud, and a hairline crack ...