It's been a year since the death of her husband, Henry, and Emily Maxwell gathers her family in Lake Chautauqua in western New York for what will be their last vacation at their summer cottage before she sells the property. Joining her is her sister-in-law, Arlene, a retired teacher who silently mourns the passing of the lake house from her family's hands and still endures the wound of a love lost long ago. Emily's firebrand daughter, Meg, a recovering alcoholic recently separated from her husband, brings her children from Detroit, the blossoming Sarah and the timid Justin. Emily's son, Ken, a struggling photographer who has quit his job and mortgaged his future to pursue his art, comes accompanied by his wife, Lisa, who is secretly heartened to be visiting the house for the last time and not-so-secretly cool to her prickly mother-in-law - and their children, the bookish Ella and the troubled Sam.
As O'Nan inhabits the mind and heart of each member of the house through the course of their week together, he illuminates the many lives of the Maxwell family as memories of summers past resurface, old rivalries flare up, and love is rekindled and born anew by the shores of the lake.