London - It sent a chilling blast-from-the-past as Kate swept in on William's arm to a Red Top paper's party last night in a Diana copycat frock circa 1981.
All eyes were on the cleavage, of course, which 34D Diana had amply filled despite 'totally freaking out' a superstitious Prince Charles who asked at the time if 'somebody had just died'.
Last night a very flat chested Kate Middleton donned a similar eye-catching funereal frock to an equally pointless vanity beano.
"Should have stuffed some 'chicken fillets' down her push-up Wonderbra, darling," Sasha Plectrum, fashion editor at iconic celebwatch site LA HagFagSlagMag.con, commented, "the current tranny look is SO passé."
The cleavage ruffles were an exact match for the strapless Emanuel gown that newly engaged Lady Di wore to her first glam party at Goldsmiths Hall in March 1981.
The gown subsequently sold for $276,000 at an auction fundraiser after the Princess' death and has become an iconic item at a Las Vegas drag queens' dress hire agency.
Its last public airing was in 2007 when Dame Edna Everage crammed herself inside it for a US telethon.
"That look hexed - and so is Kate," Plectrum added.
Prince Charles is 104.