I can't rennet very much about it at all. I think it's maybe 50's to 70's.
Set in a hotel in Europe. Sort of glamorous golden age of film style.
One of the hotel rooms 'disappears' and all the hotel staff pretend there has never been a room with that number.
One of guests is determined to prove the room exists - they find the door hidden behind a false wall that's been decorated to look like the rest of the corridor.
Maybe some died of a contagious disease and the hotel tried to cover it up?
Not much to go on, but any ideas??