At their twenty-fifth high school reunion, four former best friends discover that growing up is way messier than anticipated--and the past isn't nearly as finished as they thought.

Back in senior year, Audrey, Micah, Jasmine and Beck were the Core Four: the lucky one, the beautiful one, the smart one, the sporty one. They had color-coded dreams, inside jokes and a lifelong friendship they thought would last forever. But graduation night ended in a tragic accident, followed by the kind of silence that stretches for decades.

Now, they've returned for their reunion, each carrying a life that looks nothing like the glossy future they imagined. There are stalled careers, complicated marriages, outspoken adult children and secrets that never fit into holiday cards. For one of them, a diagnosis of early-onset dementia turns the weekend into a ticking clock.

Across one unforgettable weekend, the Core Four must decide if their past can still change their future together.