The cherry blossoms are in full bloom in Washington, D.C., and the Calhouns are in the midst of hosting their annual party to celebrate the best of the spring season. With a house full of friends, neighbors and their beloved three adult children, the Calhouns are expecting another picture-perfect event. But a brutal murder in the middle of the celebration transforms the yearly gathering into a homicide scene and all the guests into suspects. Behind their façade of perfection, the Calhoun family has been keeping some very dark secrets. As the investigation heats up, family tensions build, and alliances shift. Long-buried resentments surface, forcing the Calhouns to face their darkest secrets before it’s too late.

One warm summer night 25 years ago, Liza Gold and her friends celebrated their high school graduation with a party on the beach. It should have been the best night of their lives, but one of them never came back out of the ocean. The tragedy haunted Liza Gold for years. Now, she's a recently divorced working mom struggling to connect with her standoffish teenage daughter, Zoe, when history repeats itself. Another young woman has drowned at Beach Week, and this time the victim is Zoe’s secret best friend. Liza begins to suspect that the two deaths are somehow related, which causes her to face hard truths and take an unflinching look at the people she’s called her closest friends for the past two decades. She must discover what really happened to both women before it’s too late.