Elvis has left the building
The show is over - go home.
This was announced at the end of Elvis Presley's concerts to encourage fans to accept that there would be no further encores and to go home. It is now used more widely to indicate that someone has made an exit or that something is complete.
Oddly, although the phrase was routinely used to encourage the audience to leave, the first time that it was announced it was to encourage them to stay in their seats. That first use was in December 1956 by Horace Logan, who was the announcer at the Louisiana Hayride show, in which Elvis was a regular performer. Presley had very quickly become very popular with teenagers but had previously taken a regular lowly spot at the Hayride, which was his first big break. He was on the bill quite early in proceedings but after his performance was over and the encore complete, the crowd of teenagers, who weren't Hillbilly enthusiasts, began to leave. Logan announced:
"Please, young people ... Elvis has left the building. He has gotten in his car and driven away ... Please take your seats"
Al Dvorin was the regular stage announcer for Elvis Presley during the 1970s. He picked up the phrase and his version can be heard on several live recordings:
"Ladies and gentlemen, Elvis has left the building. Thank you and goodnight."
The use of this term and the fact that Elvis is probably the most prominent celebrity to be known (despite claims to the contrary) to be unambiguously dead, have given rise to the verb 'to Elvis', i.e. to make a sudden exit.
The Kelsey Grammar sitcom 'Frasier' used a play on the line at the end of each show - "Frasier has left the building."