Fireflower has been helping out on Sweet Apple Acres for three weeks, and nopony really knows much about her. One time, Big Macintosh caught her writing a letter to somepony she claimed was her mother. She then threw a horseshoe at him because he was in her house.
In truth, this mysterious earth mare is a changling, and she has been sending reports of Ponyville to Queen Chrysalis. But why? Is that really what she wants to do?