Struggling New York actress Alison has an outwardly good life: toned body, plenty of dates, a comfortable daily regimen. Still, she feels stagnant, empty, and as blocked as the river view from her Upper West Side apartment. Now divorced and in her mid-30s, she has never gotten past an early childhood trauma of being torn away from her brother and sister when her parents separated. Since then, nothing sticks. No one stays. She craves a sense of permanence, a place to call home.

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.

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.

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?

It’s New Year’s Eve 1982, and Oona Lockhart has her whole life before her. At the stroke of midnight she will turn 19, and the year ahead promises to be one of consequence. Should she go to London to study economics, or remain at home in Brooklyn to pursue her passion for music and be with her boyfriend? As the countdown to the New Year begins, Oona faints and awakens 32 years in the future in her 51-year-old body.

Thirty years ago, Amelia Vaux Tanner and her husband built a house high on the bluffs, a cottage they named Chateau Laveau. For decades, “Ama” played host to American presidents, Wall Street titans, and cultural icons. But her favorite guests have always been her three “goddaughters”: Esperanza “Perry” Soto, a beautiful, talented Afro-Latina lawyer with Ama’s strong, yet guarded personality; Olivia Jones, a gifted Wall Street analyst with Ama’s brilliant, logical mind; and Billie Hayden, a gifted marine biologist and rule-breaker with Ama’s courageous free spirit.

Lark has good things coming: a career as a board-game designer and a whirlwind romance with a handsome investor, who is so compassionate and supportive, he’s almost too good to be true. Jessica has always been cautious, but she can’t resist a brilliant TED-talking visionary. Holly has settled into a comfortable life with Jack, her husband of nearly twenty years. They’ve raised three children, they own a beautiful home, and they’ve founded a worthy charity. Lark, Jessica, and Holly are three strangers with so much in common it hurts. Their one and only is one and the same.

Hannah and Finn have spent every Christmas together since college. Neither has anywhere else to go—Hannah’s parents died, and Finn’s disowned him when he came out. Their tradition of offbeat holiday adventures only grows more outrageous with time. When the pair starts their adult lives in New York City, they add stylish Priya and mysterious Theo to the group, solidifying a found family and sense of belonging they’ve always craved.

It's 1947. War's over, cherry-print dresses, parking above the city lights, swing dancing. Beautiful, 17-year-old Violet lives in a perfect world. Everybody loves her. In 2012, she's still beautiful, charming, and surrounded by admirers. Veronica "Ronni" Johnson, licensed practical nurse and aspiring writer, meets the captivating Violet in the assisted living facility where Violet requires no assistance, just lots of male attention. When she dies, she leaves Ronni a very generous bequest - only if Ronni completes a book about her life within one year.

Elisabeth, an accomplished journalist and new mother, is struggling to adjust to life in a small town after nearly 20 years in New York City. Alone in the house with her infant son all day (and awake with him much of the night), she feels uneasy, adrift. She neglects her work, losing untold hours to her Brooklyn moms' Facebook group, her "influencer" sister's Instagram feed, and text messages with the best friend she never sees anymore. Enter Sam, a senior at the local women's college, whom Elisabeth hires to babysit.

Raised outside of Boston, Ivy’s immigrant grandmother relies on Ivy’s mild appearance for cover as she teaches her granddaughter how to pilfer items from yard sales and second-hand shops. Thieving allows Ivy to accumulate the trappings of a suburban teen - and, most importantly, to attract the attention of Gideon Speyer, the golden boy of a wealthy political family. But when Ivy’s mother discovers her trespasses, punishment is swift and Ivy is sent to China, and her dream instantly evaporates.

Sometimes, the worst day of your life happens, and you have to figure out how to live after it. So Clementine forms a plan to keep her heart safe: work hard, find someone decent to love, and try to remember to chase the moon. The last one is silly and obviously metaphorical, but her aunt always told her that you needed at least one big dream to keep going. And for the last year, that plan has gone off without a hitch. Mostly. The love part is hard because she doesn’t want to get too close to anyone—she isn’t sure her heart can take it.

Ever since she can remember, Vanessa has been able to see people's fortunes at the bottom of their teacups. To avoid blurting out their fortunes, she converts to coffee, but somehow, fortunes escape and find a way to complicate her life and the ones of those around her. To add to this plight, her romance life is so nonexistent that her parents enlist the services of a matchmaking expert from Shanghai.

Assunta has given up on love. She might run her little trattoria in the most romantic mountain town in Italy, but love just seems to have passed her by. Sarah-Jane is finished with love. She's hiring an old convertible and driving around Italy this summer—it's the perfect way to forget all about her hot celebrity ex-boyfriend! But when Sarah-Jane's car breaks down in Montenello, she has to stay longer than she intended! And the trouble is, love is everywhere....