Claire has a problem with setting limits. All her life she has taken on every responsibility, assumed every burden, granted every request. Claire wants it all—and in the eyes of her friends, she has it: a devoted husband, four beautiful children, even a successful career as an artist. So when she agrees to chair the committee for Nantucket's social event of the year, she knows she can handle it. Claire can handle anything. But when planning the gala propels her into the orbit of billionaire Lock Dixon, unexpected sparks begin to fly.

Adrienne Dealey has spent the past six years working for hotels in exotic resort towns. This summer she has decided to make Nantucket home. Left flat broke by her ex-boyfriend, she is desperate to earn some fast money. When the desirable Thatcher Smith, owner of Nantucket's hottest restaurant, is the only one to offer her a job, she wonders if she can get by with no restaurant experience. Thatcher gives Adrienne a crash course in the business...and they share an instant attraction.

Birdie Cousins has thrown herself into the details of her daughter Chess's lavish wedding, from the floating dance floor in her Connecticut back yard to the color of the cocktail napkins. Like any mother of a bride-to-be, she is weathering the storms of excitement and chaos, tears and joy. But Birdie, a woman who prides herself on preparing for every possibility, could never have predicted the late-night phone call from Chess, abruptly announcing that she's cancelled her engagement. It's only the first hint of what will be a summer of upheavals and revelations.

Every summer the Newton family retreats to their beloved home on Nantucket for three months of sunshine, cookouts, and bonfires on the beach. But this summer will not be like any other. When Arch Newton, a prominent New York attorney, dies in a plane crash on his way home from a business trip, his beautiful widow, Beth, can barely keep things together. Above all, though, she decides that she must continue the family tradition of going to Nantucket, and at the same time fulfill a promise that Arch made before he died.

Marguerite Beale, former chef of culinary hot spot Les Parapluies, has been out of the public eye for over a decade. This all changes with a phone call from Marguerite's goddaughter, Renata Knox. Marguerite has not seen Renata since the death of Renata's mother, Candace Harris Knox, fourteen years earlier. And now that Renata is on Nantucket visiting the family of her new fiancé, she takes the opportunity, against her father's wishes, to contact Marguerite in hopes of learning the story of her mother's life—and death.

Kelley Quinn is the owner of Nantucket's Winter Street Inn and the proud father of four, all of them grown and living in varying states of disarray. Patrick, the eldest, is a hedge fund manager with a guilty conscience. Kevin, a bartender, is secretly sleeping with a French housekeeper named Isabelle. Ava, a school teacher, is finally dating the perfect guy but can't get him to commit. And Bart, the youngest and only child of Kelley's second marriage to Mitzi, has recently shocked everyone by joining the Marines.

Nantucket is only 11 miles away from Martha's Vineyard. But they may as well be worlds apart for estranged twin sisters Harper and Tabitha Frost. After not speaking for more than a decade, Harper and Tabitha switch islands - and lives - to save what's left of their splintered family. But the twins quickly discover that the secrets, lies, and gossip they thought they'd outrun can travel between islands just as easily as they can. Will Harper and Tabitha be able to bury the hatchet and end their sibling rivalry once and for all?

With rumors of infidelity straining Greg and Tess MacAvoy's marriage, the couple head out on their sailboat one early summer day to celebrate their wedding anniversary, hoping the roughest waters are behind them. But in an accident off Nantucket, they mysteriously drown, leaving behind two small children as well as three couples who have long been their closest friends. Tragedy brings to the surface long-simmering conflicts and emotions, and the MacAvoys' six grieving friends find themselves unprepared for the revelation of secret upon secret.

Meredith Martin Delinn just lost everything: Her friends, her homes, her social standing - because her husband Freddy cheated rich investors out of billions of dollars. Desperate and facing homelessness, Meredith receives a call from her old best friend, Constance Flute. Connie's had recent worries of her own, and the two depart for a summer on Nantucket in an attempt to heal. But the island can't offer complete escape, and they're plagued by new and old troubles alike.

It's wedding season on Nantucket. The beautiful island is overrun with summer people - an annual source of aggravation for year-round residents. When one lavish wedding ends in disaster before it can even begin - with the bride-to-be discovered dead in Nantucket Harbor just hours before the ceremony - everyone in the wedding party is suddenly a suspect. As Chief of Police Ed Kapenash digs into the best man, the maid of honor, the groom's famous mystery novelist mother, and even a member of his own family, the chief discovers that every wedding is a minefield - and no couple is perfect.