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.

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.

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.

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.

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?