In a suite on the top floor of a luxury hotel somewhere.

Beep! Beep!

An electronic lock was unlocked, and the door was pushed open. A middle-aged man walked in and came to the very luxurious living room in the suite. He sat down next to a door with an express door lock installed. He was silent, thinking, and motionless.

After a long while-

"Knock, knock, knock..."

There was a knock on the door, which woke up the ...