The year is 1860. Twelve-year-old Louisa Taylor Gates lives on a farm near the small town of Burley, Maryland. Burley, as well as the rest of the United States, is deeply divided on the issue of slavery. Louisa learns about the quilt code from her family members, ardent abolitionists, who are conductors on the Underground Railroad and move slaves to freedom. Pursued by slave catchers who want to punish her and betrayed by a neighbor who spies on her, Louisa repeatedly places herself in mortal danger. She overcomes fire and freezing cold, as she enthusiastically joins the effort to smuggle slaves out of bondage. The country is on the brink of civil war, and in spite of her youth, Louisa risks her life, determined to do her part for the cause she believes in.