The portal to the high school in another world of Equestria closed after Twilight Sparkle and Spike made it back to their world and closed for another 30 moons. Now, two and a half years later, the portal opens once again and out of it comes, Twilight...? What? She already made it back didn't she?

It turns out that the Twilight from the other world asked Twilight to save the school from turning into a wasteland filled with miserable people that don't care about friendship.

And to make matters worse, she once again has a time limit. She has to save the school, and get back to her world before the portal closes for another 30 moons, or she will be stuck in that world forever, and that is something she can't let happen.