One evening working late in the office, my colleague asked me to open the door for him to enter to get some hot water. When we were chatting for a while, we both hear our boss room there were sound of keys & knob turning ... he asked if boss in? I answered 'no', he's gone overseas. We both left the office immediately without thinking. (Memory collected at the Public Libraries during the "irememberGhost stories" campaign from 27 Sep to 30 Nov 2012)