Three hundred forty-two people in his building, maybe nearby houses, maybe the coffee shop across the street—all of them watching whatever his TV played. But his TV wasn’t playing anything. He was the channel now.

A knock on the door.

Then he found it:

“Who is it?”

He should have uninstalled it then. But the mod had a feature the original never had. Hidden in the settings menu, behind a seven-second long-press of the OK button, was an option labeled:

Leo lived in a 24-story apartment building. Five hundred meters covered half the neighborhood.

Three knocks. Then two. Then one.