Where I End and You Begin.

there's a gap in between
there's a gap where we meet
where i end and you begin

and i'm sorry for us
the dinosaurs roam the earth
the sky turns green
where i end and you begin

i am up in the clouds
i am up in the clouds
and i can't and i can't come down

i can watch but not take part
where i end and where you start
where you, you left me alone
you left me alone.

X' will mark the place
like parting the waves
like a house falling into the sea.

I know some people may not like this kind of music, but I just can't forget the bassline.
In the film there is a piano-like instrument. It is called Ondes Martenot. This is "an early electronic musical instrument with a keyboard and slide, invented in 1928 by Maurice Martenot", according to Wikipedia. This instrument is responsible for the freak high-pitch noise in the song.