When Fern Douglas sees the news about Astrid Sullivan, a thirty-four-year-old missing woman from Maine, she is positive that she knows her. Fern's husband is sure it's because of Astrid's famous kidnapping - and equally famous return - twenty years ago, but Fern has no memory of that, even though it happened an hour outside her New Hampshire hometown, where she's returning for the week to help her father pack for a move. And when Astrid appears in Fern's recurring nightmare, one in which a girl reaches out to her, pleading, Fern fears that it's not a dream at all, but a memory. Back home in New Hampshire, Fern purchases a copy of Astrid's recently published memoir Behind the Red Door- which may have provoked her original kidnapper to abduct her again- and as Fern reads through its chapters, visits the people and places within it, she discovers more evidence that she has an unsettling connection to the missing woman. As her search becomes increasingly desperate, she hopes to remember her past so she can save Astrid in the present--before it's too late.