Alex Marks's carefully cultivated world is upended when her childhood hero, Francis Keen, is brutally murdered. Francis was the woman behind the famous advice column Dear Constance, and her words helped Alex through some of her darkest times. When Alex sees an advertisement searching for her replacement, she impulsively applies. Alex is given the position, but soon she begins to receive strange, potentially threatening letters. As Alex is drawn into the details surrounding her predecessor's murder, she finds herself trapped in a dangerous game of cat and mouse that takes her all the way to Francis Keen's summer house, where the killer may just be waiting for her.