Threshold Zero

It starts with a silence so deep it stops the human heart.

At midnight, in cities across the globe, the world holds its breath. For sixty seconds, all sound vanishes. Electronics freeze. The hum of civilization dies. And in that terrifying quiet, a visitor arrives.

He is a child in a yellow raincoat. He knocks once. If you open the door, he offers you a gift-and a burden.

In Nairobi, signal analyst Zola Mbeki captures a frequency that shouldn't exist-a broadcast from the end of the world. In T...