It is twelve years before Princess Luna's return, and Redheart is a young mare, in her final year of high school. She has aspirations of joining the Equestrian Marines to see the world, then going on and attending a nice university. Her dream is to attend medical school, interested in cardiothoracics.

However no plan survives first contact with the enemy, and Redheart becomes a field medic serving Princess Celestia in a bloody war.