Imagine throwing a surprise dinner party for thousands of your closest friends. 

Over 4,000 New Yorkers dressed in all white for a dinner party in Bryant Park on Wednesday night. The "Diner en Blanc" event marked its 25th anniversary this year. New York has participated for the third year in a row.

According to CBS News, the event has thousands lugging tables, chairs and food to a locations that remained a secret until minutes before participants sat down. Individuals were asked to bring their own set up, which also included cutlery, glasses and white tablecloths.

The most important rule was that all participants must wear all white

"Diner en Blanc," or "dinner in white" is known as a flash mob dinner party that originated in Paris 25 years ago.

According to "Dîner en Blanc" Facebook page, over 12,000 people in 40 cities around the world participate in the event every year. They all get together for a spontaneous evening of fine dining. François Pasquier, a Parisian, and his friends, created the concept of Dîner en Blanc.

The event is now celebrated in 16 cities across the United States

Today, it's celebrated in over 16 cities across the U.S. and it's growing. The rules are simple: you sign up on the website, if you get selected to participate you will be allowed to know the date of the event; however, the location is only disclosed just a few hours prior to the dinner.

Dîner en Blanc is organized by local groups who discovered a passion for the event. It is also the subject of a documentary "Dîner en Blanc: the World's Largest Dinner Party," showing how it has evolved into a "mesmerizing convergence of food, fashion, and friendship," according to the organizers.

"Thirty thousand New Yorkers put their names on a waiting list on the first year - 15,000 additional this year," organizer Sandy Safi told CBS. "So we're at 45,000 people just wanting to do something special and different."