The song was originally sung on 1937's show, "Babes In Arms". That shaw had introduced few more nice songs as; "My Funny Valentine"; "The Lady is a Tramp"; "Johnny One Note" "I Wish I Were in Love Again" and more.
In 1939, it was sung in the same titled film.
As the lyric have some mystic moods, it could be solved by reading the verse (written at the end of this notes). This love song is so marvelous while the verse wasn't sung.
It seems we stood and talked like this before We looked at each other in the same way then But I can't remember where or when
The clothes you're wearing are the clothes you wore The smile you are smiling you were smiling then But I can't remember where or when
Some things that happened for the first time Seem to be happening again
And so it seems that we have met before And laughed before, and loved before But who knows where or when?