It's 1775 in Mexico, New Spain, and 15-year-old Fernanda Marquina, of Spanish and Pima Indian ancestry, can't seem to live up to her mother's expectations or fit into the limited female roles of her culture. To escape, Fernanda grabs any opportunity to ride the horses she loves. At a greater cost than she could ever have imagined, her dream of adventure in faraway lands is realized. With her family, Fernanda joins Juan Bautista de Anza's historic colonization expedition to California. On the arduous four-month journey, Fernanda makes friends with Feliciana, the young widow Fernanda can entrust with her deepest thoughts; Gloria, who becomes the sister Fernanda always wished for; and Gloria's seductive brother Miguel, gentle one moment, angry the next and, like Fernanda, a mestizo-half Indian and half Spanish. As Fernanda penetrates Miguel's layers of hidden feelings, she's torn between him and Nicolas, the handsome Spanish soldier hoping to win her heart. But propelling Fernanda along the journey is her search for Mama's Pima Indian past, a past Mama refused to talk about, a past with secrets that Fernanda is determined to learn. The truths she discovers will change the way she sees her ancestry, her family, and herself.