A hidden door provides hidden access to a secret room.
The secret room can fulfill different functions. It can be used as a panic room or protect your valuables from prying eyes.
The door adapts to the wall and remains almost invisible. Also, a camouflage of the door as a picture, cabinet or bookshelf is possible.
Likewise, existing rooms can also be divided by retracting a wall. With a hidden door you get a hidden new room which can be used in case of a home invasion.