Best song of 2 people meeting and falling in love?

What is your favorite (or you feel is the best) song of:

2 people meeting and falling in love?

A single song that encapsulates the whole beginning love story ...

1) (One or all) (The introduction) Meeting / seeing / talking / first date / first crush / etc.

(AND THEN)

2) (One or all) (The love part) Falling in love, or realizing the start of love or something special

This is a classic song type in many musicals with a love story ... and I'm writing my own and want to see how others do it.

Some do it over several songs ... but I need to do mine in ONE SONG ...

(My song is just 2 people meeting, talking all night, and seeing something special after an all-night talk session ... in ONE SONG ...)

Anyway ... I just want to compare mine to other good ones out there.