Flag on the play

Posted by Niklas on April 17, 2002

Hi,
I'm translating "The Sopranos" for Swedish television viewers, and need an explanation of "flag on the play".
(A female psychiatrist has happened to double-book her clients, and when she enters the waiting room one of them says: "Flag on the play. I'm pretty sure you said Tuesday." I've tried the various on-line slang dictionaries, but had no luck.
Hilfe!

Niklas