for old times' sake
Ilsa: Play it once, Sam. For old times' sake.
Sam: [lying] I don't know what you mean, Miss Ilsa.
Ilsa: Play it, Sam. Play "As Time Goes By."
Sam: [lying] Oh, I can't remember it, Miss Ilsa. I'm a little rusty on it.
Ilsa: I'll hum it for you. Da-dy-da-dy-da-dum, da-dy-da-dee-da-dum...
[Sam begins playing]
Ilsa: Sing it, Sam.
Sam: [singing] You must remember this / A kiss is still a kiss / A sigh is just a sigh / The fundamental things apply / As time goes by. / And when two lovers woo, / They still say, "I love you" / On that you can rely / No matter what the future brings-...
Rick: [rushing up] Sam, I thought I told you never to play-...
[Sees Ilsa. Sam closes the piano and rolls it away]