Thirteen-year-old Martha Bartlett insists on being a part of the Underground Railroad rescue to bring her brother Jake back home to their abolitionist community in Connecticut. It's 1860 and though African-Americans and mixed-race peoples in the north are supposed to be free, seven-year-old Jake, the orphan of a fugitive slave, is kidnapped by his "owner" and taken south to Maryland. Jake is what we'd now describe as on the autism spectrum, and Martha knows just how to reassure him when he's anxious or fearful. Using aliases, disguises, and other subterfuges, Martha artfully dodges Will and Tom, the slave catchers, but struggles to rectify her new reality with her parents' admonition to always tell the truth. She must be brave but not reckless, clever but not dishonest. But being perceived sometimes as white, sometimes as black during the perilous journey has thrown her sense of her own identity into turmoil. Alonso combines fiction and historical fact to weave a suspenseful story of courage, hope, and self-discovery in the aftermath of the Fugitive Slave Act of 1850 while illuminating the bravery of abolitionists who fought against slavery.