I saw a movie when I was little and I think Fred MacMurray was in it. It was in black & white and I remember there was a riddle they were trying to figure out. Some of the words in the riddle were: knobs-es, keys-es. This was about 40 years ago and I have never been able to figure out what it is called. It was probably from the late 1930's or early 1940's.