Imagine you're dressed in your finest white threads, gourmet picnic basket in hand, champagne flutes, chair and table too - all white of course. You don't know yet where you're headed, but there's a frisson of excitement in the air, as you spot numerous similarly-clad picnic-goers converging en masse at a beautiful, public location - it could be Paris's Champs-Elysees, the sands of Bondi Beach, or Central Park in New York.
Lining your table and chairs up in perfect order, you unpack your picnic basket, pop your wine cork, and, after the waving of a cloth napkin, proceed to take part in the world's poshest picnic.
The idea of Diner en Blanc is for guests to take over a public space, have a perfectly orchestrated, absolutely elegant picnic, before packing up their baskets, leftovers and rubbish and leaving the space as it was found. The evening follows a set of rules in keeping with the court-like tradition it has become renowned for.
According to the website, guests are to "conduct themselves with the greatest decorum, elegance, and etiquette", and to keep within the core values of secrecy, friendship, equality, elegance and gallantry. Plastic or paper plates are forbidden, as are any coloured or black items of clothing.