Ten years ago, Equestria was nearly destroyed in a combined invasion of its worst enemies. Only with the timely intervention of its erstwhile human allies was the nation spared slavery and extinction. The war is over now, and the treaties of peace faithfully followed even after a decade. While earth ponies help rebuild Earth's ecosystem, human tractors erect roads and cities with terrifying speed.
Sweetie Belle helped make victory possible, but the cost of that victory was one of her best friends. Equestria is safe now, and ponies are spreading to the stars. Why doesn't she feel happier?
When a remarkable spell summons a human mind into the body of a unicorn filly, Princess Twilight Sparkle does the only thing she can think of: Take on an apprentice.
When Equestria is threatened with an invasion of all its greatest enemies, Celestia and Luna are forced to turn to the only ally with a chance of helping them: Humans. The only question left now is whether any of Equestria will be left to save.
Second Chance has her memories back, and now the responsibility of an entire civlization rests on her shoulders. Can she save her old world without betraying her new one?
Ten years have passed since the awful war that nearly destroyed Equestria. Humanity and ponies now live together in harmony. Yet for Sweetie Belle, not all scars are so easily healed.