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?

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.

Irene Steele shares her idyllic life in a beautiful Iowa City Victorian house with a husband who loves her to sky-writing, sentimental extremes. But as she rings in the new year one cold and snowy night, everything she thought she knew falls to pieces with a shocking phone call: her beloved husband, away on business, has been killed in a helicopter crash. Before Irene can even process the news, she must first confront the perplexing details of her husband's death on the distant Caribbean island of St. John.

After uprooting her life in the States, Irene Steele has just settled in at the villa on St. John where her husband Russ had been living a double life. But a visit from the FBI shakes her foundations, and Irene once again learns just how little she knew about the man she loved. With help from their friends, Irene and her sons set up their lives while evidence mounts that the helicopter crash that killed Russ may not have been an accident.

Welcome to the most tumultuous summer of the 20th century. It's 1969, and for the Levin family, the times they are a-changing. Every year, the children have looked forward to spending the summer at their grandmother's historic home in downtown Nantucket. But like so much else in America, nothing is the same.

A warm June evening, a local tradition: The students of Nantucket High have gathered for a bonfire on the beach. But what begins as a graduation night celebration ends in tragedy after a horrible car crash leaves the driver of the car, Penny Alistair, dead and her twin brother in a coma. The other passengers - Penny's boyfriend Jake and her friend Demeter - are physically unhurt, but the emotional damage is overwhelming, and questions linger about what happened before Penny took the wheel.

From marriage, infidelity, and the mayhem of motherhood to scandal, tragedy, and illness - three women seek peace and comfort in Nantucket as they cope with life's challenges. Three women - burdened with small children, unwieldy straw hats, and some obvious emotional issues - tumble onto the Nantucket airport tarmac one hot June day. Vicki is trying to sort through the news that she has a serious illness. Her sister, Brenda, has just left her job after being caught in an affair with a student. And their friend Melanie, after seven failed in vitro attempts, is pregnant at last.

After a string of bad dates and no prospects, Sophia Othonos has finally hit the jackpot: an actual nice guy. When he suggests a romantic getaway, she’s sure they’re about to take the next step toward their future. A rustic cruise to the Galápagos Islands isn’t exactly her idea of a vacation, but Sophia is ready for anything…until her boyfriend has to cancel. Now she’s all alone on a trip that was meant for two. Sophia finds herself at a crossroads about who she is, what she wants, and whether her relationship is really everything she thought.

Fresh off a bad breakup with a longtime boyfriend, Nantucket sweetheart Lizbet Keaton is desperately seeking a second act. When she’s named the new general manager of the Hotel Nantucket, a once Gilded Age gem turned abandoned eyesore, she hopes that her local expertise and charismatic staff can win the favor of their new London billionaire owner, Xavier Darling, as well as that of Shelly Carpenter, the wildly popular Instagram tastemaker who can help put them back on the map.

When Mallory Blessing's son, Link, receives deathbed instructions from his mother to call a number on a slip of paper in her desk drawer, he's not sure what to expect. But he certainly does not expect Jake McCloud to answer. It's the late spring of 2020 and Jake's wife, Ursula DeGournsey, is the frontrunner in the upcoming Presidential election. There must be a mistake, Link thinks. How do Mallory and Jake know each other?

Hollis Shaw, creator of the popular food blog, Hungry with Hollis, is shocked when her heart surgeon husband, Matthew, is killed in a one-car accident on a snowy morning. The cracks in Hollis’s perfect life—her strained marriage and her complicated relationship with her daughter, Caroline—grow deeper. So when Hollis hears about something called a “Five-Star Weekend”—one woman organizes a trip for her best friend from each phase of her life: her teenage years, her twenties, her thirties, and midlife—she decides to host her own Five-Star Weekend on Nantucket.

On a perfect June day, Vivian Howe, author of 13 beach novels and mother of three nearly grown children, is killed in a hit-and-run car accident while jogging near her home on Nantucket. She ascends to the Beyond where she's assigned to a Person named Martha, who allows Vivi to watch what happens below for one last summer. Vivi also is granted three “nudges” to change the outcome of events on earth.

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.

Lyn, Cat, and Gemma Kettle, beautiful 33-year-old triplets, seem to attract attention everywhere they go. Together, laughter, drama, and mayhem follow them, but apart, each is dealing with her own share of ups and downs. Lyn has organized her life into one big checklist, Cat has just learned a startling secret about her marriage, and Gemma, who bolts every time a relationship hits the six-month mark, holds out hope for lasting love.