This is a storage room with a built in trap. It is designed a way that allows only users that know about the hidden button inside to use the room without activating the trap. If you only press the button outside the door will open, and everything will look just fine, but after a given time it will close again and the floor will open, and the user will fall to a horrible death (optional). However if you activate the secret button inside within the given time the trap will get deactivated, and you can have a fantastic day.