Dr. Yvette Running Horse Collin is a Lakota scientist who studies the history of Native Americans and horses. Through her research, she is challenging the dominant narrative that horses went extinct on this continent in the last ice age and did not reappear until European explorers came to the New World. Ashley joins Dr. Running Horse Collin on her ancestral lands in the Black Hills of South Dakota during the time of the Sundance Ceremony. Meanwhile, back at the ranch, Boo and Ashley nap in the sun and reflect on trust and love and adventures to come.