The Color of Frost tells the story of Nina DeMarco, an adopted twenty-seven-year-old woman suffering from anxiety and depression. As the story unfolds, Nina begins to overcome the despair of her failed marriage by challenging herself to find the owner of a series of letters she finds hidden in the crawlspace of her new attic apartment. Nina feels connected to the author of the letters, a mysterious Lilia Michaud, the woman who once lived there. While the two women are born decades apart, Nina becomes fascinated by Lilia's unconventional life, having escaped an abusive guardian when her uncle comes and rescues her. 

The Color of Frost alternates between Nina's story, which takes place in 1974, and that of Lilia throughout periods of her life that she documents in the letters. However, common threads emerge that unexpectedly link the two women. The Color of Frost is part mystery and part historical fiction, with the year 1974 connecting the reader with relevant themes that are featured prominently in today's headlines.