You begin looking towards an archway in a white wall. Turn around to your right and proceed away from the archway down the hall. Keep going until you hit a few steps, don't go up the steps, instead turn to your right and move into that doorway. You should be entering a bathroom. Take the immediate right, before you get into the room with the sink proper, and you should enter a walk-in closet. Step inside this closet and you're done.