"We pledge ourselves to Equestria,
To be the first that bleed when the nation suffers,
To be the first to fall in its defence,
To be the avengers when it is wronged.
We are Celestia's eyes in the dark,
We are Celestia's hooves beyond her reach,
We are Celestia's will in lawless land,
Until we cannot do more."
~ Dawn Guard Oath
It has been 200 years since the climatic battle between the sisters, and Princess Celestia is still reeling emotionally from the war that consumed Equestria, leaving her distant and paranoid. To make sure that the tragedy would never repeat itself, she had formed the Dawn Guard soon after the battle to find the wicked wherever they might be found, and end all threats to the land and it's Princess.
Celerity was born into this world, and wants nothing less but to live up to the example her grandfather, a legendary leader of the elite group, set for her. As she struggles for her goal, it becomes apparent that others have designs for her too, and she will have to learn the cost of defying them.