As you pull the switch, you close your eyes and hope nothing terrible happens. You hear a loud creaking sound and notice that the door in the room has opened. Thankful that you chose the right switch, you race through the open doorway and come upon a long staircase leading up. Before you take your first step, the door behind you closes shut with an ominous click. Certain that the door is now locked, you make your way up the staircase.