Margaret Simon, almost 12, has just moved from New York City to the suburbs, and she’s anxious to fit in with her new friends. When she’s asked to join a secret club, she jumps at the chance. But when the girls start talking about boys, bras, and getting their first periods, Margaret starts to wonder if she’s normal. There are some things about growing up that are hard for her to talk about, even with her friends. Lucky for Margaret, she’s got someone else to confide in...someone who always listens.

Sandy Pressman is a nice suburban wife whose boredom is getting the best of her. She could be making friends at the club, like her husband keeps encouraging her to do. Or working on her golf game. Or getting her hair done. But for some reason, these things don't interest her as much as the naked man on the motorcycle.

In the summer of 1977, Victoria Leonard’s world changes forever when Caitlin Somers chooses her as a friend. Dazzling, reckless Caitlin welcomes Vix into the heart of her sprawling, eccentric family, opening doors to a world of unimaginable privilege, sweeping her away to vacations on Martha’s Vineyard, an enchanting place where the two friends become “summer sisters”. Now, years later, Vix is working in New York City. Caitlin is getting married on the Vineyard. And the early magic of their long complicated friendship has faded.

When Deenie finds out that she has scoliosis, she’s scared. When she sees the brace for the first time, she wants to scream. But the words won’t come out. And Deenie, beautiful Deenie, who everyone says should be a model, is stuck wearing a brace from her neck to her hips. For four years—or longer. She never worried about how she looked before—how will she ever face the hard times ahead?

Karen Newman has decided she’ll never get married. Just look at her parents. All they do is fight. And now Karen’s dad has moved out of the house and he and her mom are talking about divorce. Her older brother has locked himself away in his room, her little sister is a mess, and she can’t bring herself to talk about any of it with her best friend. She’s never felt so alone. Yet in spite of everything Karen is sure she can set things right again if only she can get her parents together in the same room. Or will her fantasy backfire?