We'll Meet Again is a love song made famous by British singer Vera Lynn with music and lyrics by Ross Parker and Hughie Charles. It is one of the most famous songs during the World War II era, and it resonated with the soldiers of the Second World War to fight for their families and sweethearts. The song has a long history of being performed in film and television.
In "Weirdmageddon 3: Take Back The Falls," Bill unfreezes Ford Pines after having turned him to gold and brought him to the Fearamid in the previous episode. Upon unfreezing him, Bill rises out of the floor playing a piano and singing a brief section of the song.
We'll meet again,
Don't know where, don't know when,
But I know we'll meet again, some sunny day.