They came, dressed in white, and in their hundreds. They ate, drank and danced.
And, at the stroke of midnight, they left, melting into the dark - leaving no trace, like so many pale spectres.
So it was on Saturday evening, Melbourne's first outing of the global phenomenon Le Diner en Blanc, or the Dinner in White; equal parts mystery tour, flash mob, pop-up feast and a large sprinkling of je ne sais quoi.
In keeping with the gala's tradition, the location of the "tres chic picnic" was only revealed to the 1000 guests moments before the event - eventually unveiled as the grassed area of the Melbourne Convention and Exhibition Centre.
Groups of 100 to 300 people gathered, as instructed by the secretive organisers, at rallying points across the city, and were given instructions to make their way by foot or bus to the picturesque setting.
Guests provided their own epicurean feasts, tables, chairs, fine china, silverware and white tablecloths - and were provided with live music, dancing, white balloons and a night to remember.
All attendees were asked to dress in formal white attire and to a man, woman and child, they obliged, making for a stunning scene on the banks of the Yarra.
The epicurean event has become world-renowned for its sophisticated mystique and elegant imagery. Unsurprisingly, it began in France, originally as an informal picnic held by François Pasquier, now 71, in Paris in 1988.
The list of friends was long, so he asked everyone to wear white so they could find each other.
The chic dinner continued year on year in Paris and then spread to Canada in 2006, before making the big time in New York in 2011.
Pasquier's son, Aymeric, now runs Diner en Blanc International, which helps host events in 50 cities, including Miami, Sydney, Chicago, Singapore, Mexico City, Johannesburg, Montreal, Abidjan and Stockholm - with more than 100,000 guests attending events around the world - clad all in white, of course.
Aymeric Pasquier said he was more than comfortable with extending his father's vision to Melbourne.
"Melbourne's culture is a reflection of Diner en Blanc's core values," he said.
"We feel that this first edition will be a true success in bringing Melburnians together and highlighting the beauty of their city."
The evening - an ambitious project in both scope and the need for secrecy - was a success, on all indicators, according to organisers.
"As the cultural capital of Australia, we felt Melbourne was primed for such a fantastic event especially since Melburnians have fallen in love with the 'pop-up' concept," co-organiser Mikaela Smith-Chandler said.
"As a city, we are renowned for being passionate about food, wine, fashion and all things stylish, so we were confident that Melburnians would embrace the event's raison d'etre.
"In essence, Diner en Blanc promotes friendship, elegance and gallantry. Over the course of the evening, the diners enhance the function and value of their city's public space by participating in the unexpected."
VIPs were trotted out for the occasion, stylishly styled and dressed in white by Hugo Boss.
The "faces and names" sequestered in the red-roped area included Shane Crawford, Damian Barrett, Dave Hughes, Shane Warne, Gary Sweet, Firass Dirani, Rhys Muldoon, Eddie McGuire, Shaynna Blaze, Scott Cam, Shelley Craft, Rebecca Judd, Hamish Blake and a sprinkling of the Real Housewives of Melbourne cast.
A lone trumpet, echoing over the Yarra, heralded the end of the evening, signalling to guests to pack up their crystal, dinnerware and tables, pick up their litter and head into the night, leaving behind no sign of their elegant revelry.