The Door of Many

Keng moved into the lit room. White floor tiles sprawled across the floor as dark stone bricks continued across the walls. He noticed a wooden door in the middle of the room. It was six and a half feet tall and about four feet wide. 

It was a brown door that had a golden doorknob on it. Keng slowly circled it, noticing the other side was white with a silver handle. 

"What the heck is this?" Keng asked. He made his way back to the beginning, taking a long glance at the doorknob.  He twisted the doorknob. It was locked. 

"Huh." He casually let out, circling to the other side. The white and silver doorknob greeted him as he put his hand on the doorknob and twisted. It opened, swinging inwards towards the right.

Blocks of stone slabs  spread evenly in front of him as he stepped through. He closed the door behind him and noticed something moving below the stone slabs.