Jerry and Elaine go to visit Jerry's parents, Morty and Helen Seinfeld, in Florida for the weekend. Morty's friend Jack Klompus comes over to pay Morty back for a dinner they had together. They argue over who ordered what and how much it cost. Jerry admires Jack's pen, a NASA pen astronaut's use that writes upside down. Jack offers the pen and Jerry accepts, upsetting Helen who claims he shouldn't have accepted because Jack didn't really want to give it to him and only offered because he assumed Jerry would refuse.
After difficulty figuring out sleeping arrangements, Elaine sleeps on an uncomfortable sofa bed, while Jerry sleeps on a small love seat. The condo is excruciatingly hot because the Seinfelds never turn on their air conditioning. A bar on the sofa bed causes back problems for Elaine, making her unable to go scuba diving with Jerry. She begs Helen to turn the air conditioning on.
A neighbor comes over and asks Jerry about the pen. Apparently, all the neighbors are gossiping about how Jerry made Jack give him his pen. Jerry's capillaries burst while scuba diving, giving him two black eyes. The air conditioning is finally on, but Helen is freezing cold. Jack comes over and Jerry returns the pen. Morty yells at Jack for taking the pen back and they argue.
They all go to a ceremony appointing the new president of the condo community. After taking too many muscle relaxers, Elaine acts loopy, stumbling around and laughing. When she's introduced to Uncle Leo's wife, Stella, she repeating yells "Stella!" like in "A Streetcar Named Desire." Jack criticizes Morty's reign as president of the condo community and they begin to argue about the pen in front of everyone. Jerry tries to get people to stay by starting his comedy act. Elaine passes out on the table, then awakens and yells "Stella!" again. She sees a chiropractor who recommends she stay with the Seinfeld's another five days to avoid aggravating her back injury.