When a strange book is found in the depths of the library's basement, a mysterious entity is released unto the unsuspecting population of Ponyville.
Shortly after this strange turn of events, Fluttershy finds comfort in a new friend who is not quite what she seems. Having loved and experienced heartbreak has left her in a near crippling state of depression that has distanced her from her friends, but is this new pony a remedy, or the source of more ailment? Just how far will Fluttershy go to know happiness again?
As everything spirals out of control, and Twilight Sparkle struggles to find a solution, she will learn that the answers she needs don't always come from books or teachers, and that there will come a time when the road must be walked without guidance.
Applejack must deal with loss and Rainbow Dash is forced to confront her past, while together they learn that there is more to a relationship than attraction and affection, and that love is anything but easy.
Pinkie Pie's upbeat outlook is cracked when her good humor is not enough to help her friends in their darkest times, and while Rarity has always acted with determination in all things, she realizes that not every decision made is necessarily the right one.
The girls are forced to leave their innocence behind as the bonds of their friendship are tested, and the sun sets on an era of peace. Dire conflict looms on the horizon.