Earth.
The neighborhood was quiet, silent as a grave yard. Like a typical neighborhood around here. There was a particular large building which looked like a long hall. It was the only distinct building in the midst of the duplexes surrounding it.
On the surface, it seemed as though there no life in the building. Naturally, every building on earth, within the borders of the ULTINUM project, looked like that. Since everyone was inside busy playing the games, there was no point wandering about.
Those who got tired and decided to find out whether or not there were people around somewhere, were tracked down and locked in the game. Done smoothly and without a trace.
"Attention you all. Attention."
A pre-recorded voice came from a circular speaking bot hanging in a corner of Hall's wall, inside the hall.
The voice of whoever it was didn't get out of the building. The building reasonably had soundproof walls.