The girls are invited to the unlikely wedding of Carrie's supposedly gay friend, flamboyant lounge singer Bobby Fine to society lady Bitsy Von Muffling. Stunned by the news, Carrie thinks about what it takes to make a relationship work. She asks: When it comes to saying 'I do,' is a relationship a relationship without the zsa zsa zsu (aka: that special something that gives you butterflies in the stomach)?
Charlotte's new 'just sex' partner, Harry, invites her to be his date for the big Hamptons wedding. Charlotte worries about his crass behavior, but accepts provided that hairy Harry wax his back. In another not so clear relationship, Miranda inexplicably finds herself having sex with Steve. Meanwhile, Samantha calls upon the services of her ex, Richard, in another way: she arranges to throw a party at his house in the Hamptons.
On the way out to the Hamptons, Carrie runs into Jack Berger, who tells her he broke up with his girlfriend. Carrie can't help but feel that zsa zsa zsu. At Samantha's fabulous pool party, Carrie and Berger have a heart to heart about relationships past, but it's too much for Berger to handle and he departs suddenly and swiftly. Carrie wonders if she should just throw in the towel and settle for a so-so relationship. Samantha struggles to enjoy herself because of the appearance of three of Richard's bikini-clad bimbo babes. She accuses the party-crashers of freeloading but realizes that she herself is still hurting over the end of her affair with Richard.
At Bobby and Bitsy's wedding, the girls find themselves moved by the mutual love of the bride and groom. It appears Bobby and Bitsy do have the zsa zsa zsu. Obviously inspired, Charlotte tells Harry mid-dance that she may be falling in love with him. He says he shares her feelings but that he's Jewish and he has to marry a Jew. Also on the dance floor, Berger tells Carrie that he'd like to go on a date with her before they break up. Carrie is reminded why she refuses to settle for anything less than butterflies.