Mysterious Footsteps in the Night

In the dark of night, Zhang Yi heard persistent footsteps wandering around in his room. He switched on the light and thoroughly searched the room, only to find that there was no one else but him.

However, the sound of footsteps continued, as if they were coming from downstairs or even within his own house.

After some contemplation, he decided to lie down on the floor, pressing his ear against the floorboards to listen closely.

This time, he could clearly hear it—the footsteps were indeed originating from downstairs, separated by only one floorboard.