Children's book author Agnes Lee is determined to complete what she knows will be the final volume of her Franklin Square novels; and even more consuming, to permanently protect a peninsula of majestic coast in Maine. To donate the land to a trust, Agnes must convince shareholders to dissolve a generations-old partnership—and one of those shareholders is her best friend, Polly Wister. As Agnes reflects on her life, long-buried memories and secrets from come to light that with consequences for all, including Polly.