Princess Twilight Sparkle wakes up to find herself in an alternate Equestria, where everypony is nice, nothing ever bad happens and everything is just 'perfect'. Naturally the place bores her to death.
After being awoken by a loud and obnoxious alternate version of herself, Celestia visits the parallel universe her alternate self is from, to tell her egotistical copy of herself to shut up.
The Ponies had succeeded in converting every Human into Ponies. However, two strange unstoppable white walls of death are now expanding across Equus and Earth.