While her sister fights to hold on to the family legacy, Louisa Highwood works tirelessly to save the lives of wounded soldiers. Putting her own safety on the line, she covertly ventures behind enemy lines to procure desperately needed supplies for the army hospital. Meanwhile, with no place of refuge left, Jesselynn and a ragtag band of freed slaves and Thoroughbreds head west on the Oregon Trail, unable to imagine what awaits them.