Sunny Starscout's ongoing search for Equestria's ancient past sends her up to the northern arctic, where it is written that a city protected by love once stood.
After their history-making adventure, Sunny decided to travel further with her friends to solve Equestria’s ancient history. However, they didn’t expect to meet a resident from the world’s past.
A human teen robbed of his home and species. A world of magic and friendship facing an unseen foe. And an experiment that could put the whole Universe in danger.
Exactly ninety days have passed since Sunny Starscout did the impossible and reunited ponykind. Once her lighthouse is rebuilt, she finds an old book in Bridlewood, and discovers that a pony has been watching all along.