After her daughter, Chess, breaks off an engagement and her fiance šubsequently dies in a rock-climbing accident, divorcee Birdie Cousins encourages her younger daughter, Tate, and her sister, India, to join her and Chess on Tuckernuck Island for a month, a time when deep secrets are soon revealed.

The ties between women can run as deep as the ocean-but so can the secrets.
For 20 years, Kayla, Antoinette and Val have performed their own special summer ritual. Once a year, the old friends put aside their daily, separate lives to drink champagne, swap stories and swim naked under the Nantucket stars. But on one of those bonding nights, one of their trio swims out from the shore and doesn't return. After the surviving friends emerge

...

"Set against Nantucket's Great Fire of 1846, this sweeping, emotional novel brings together three courageous women battling to save everything they hold dear... Nantucket in 1846 is an island set apart not just by its geography but by its unique circumstances. With their menfolk away at sea, often for years at a time, women here know a rare independence -- and the challenges that go with it. Eliza Macy is struggling to conceal her financial trouble...