Niamh Braunwen is a new student at Canterlot High, having just transferred when her mom retired from the navy. On her first day, she meets the other new student, Sunset Shimmer. Niamh now must do her best to navigate a new school, deal with Sunset's darker actions and moods, and the weird cube her Aunt Sandy gave her that is starting to glow, and a seventy year old conspiracy theory turning out to be true.