The iconic dress Marilyn Monroe wore to sing Happy Birthday, Mr President to JFK in 1962 is to cross the block at Julien's Auctions.
Designed by Bob Mackie and Jean Louis, the dress is decorated with 2,500 crystals (all applied by hand) and was so tight the star had to be sewn into it.
Monroe's performance that night has passed into legend, despite lasting just a couple of minutes.
Her breathy, sultry delivery led to immediate rumours she was having an affair with the president.
Tragically, this was one of Monroe's last appearances in public.
She would be found dead from an overdose at her home in Hollywood just three months later.
Auction house president Darren Julien said: "Marilyn Monroe singing 'Happy Birthday Mr. President' is certainly one of the most famous impromptu performances in American history.
"That rendition has lived on for decades as one of the most remarkable events in her career and certainly one of the most storied tales in popular culture history ��� a moment in time squarely at the center of the 1960s, Hollywood and Camelot�Ǫ
"This dress, this story, this momentous occasion represents a defining moment in history. This auction will remind the world why Marilyn Monroe remains an icon."
There will be enormous interest in the dress from collectors around the world.
When it was last offered at Christie's in 1999 it realised $1.2m - then a world record.
The buyer was investor Martin Zweig, who kept it in a specially constructed display case.
It's now expected to make around $3m.
The only comparable dress is the white one Monroe wore in The Seven Year Itch, which sold for a record $5.6m in 2011.
It's entirely possible the lot could regain the title of most valuable piece of clothing ever sold when it auctions on November 17-19.
Hours before she went onstage that night, Marilyn visited her hairdresser.
We're selling a strand of hair from that very cut, click here to find out more.
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