[4] In 2004, Serendipity celebrated its fiftieth anniversary by introducing the record-breaking Golden Opulence Sundae, listed in the Guinness Book of World Records as the most expensive dessert, at $1000.

It is made with three scoops of the Tahitian vanilla bean ice cream infused with Madagascar vanilla; covered in 23K edible gold leaf; drizzled with the world's most expensive chocolate, Amedei Porcelana; and covered with chunks of Chuao chocolate, which is from cocoa beans harvested by the Caribbean Sea on Venezuela's coast.

[8][9] On Memorial Day, May 30, 2011, Serendipity 3 opened a new restaurant on the historic corner of M Street and Wisconsin Avenue in the heart of Washington, D.C.'s popular Georgetown shopping district.

The Georgetown restaurant also featured a historical clock from landmark D.C. jeweler Galt & Bros, established in 1802 and one of the longest running businesses in D.C.,[10] as well as a 1960s photograph of Andy Warhol and Serendipity 3 co-founder Stephen Bruce.

Released in 2001, it centers on a couple that meet by chance while shopping at Bloomingdale's, and share dessert at the restaurant later that same night.

Trust the Man, released in 2006, includes a scene of David Duchovny's character being invited to Serendipity 3 by a potential love interest, and then at the restaurant on the first floor eating.

The second novel in the Gossip Girl series, You Know You Love Me, includes a scene in which Serena and Dan visit Serendipity 3 and, respectively, order a peppermint sundae and a coffee banana split.