Pinkie Pie, the peerless party pony we know and love, has always perplexed Twilight Sparkle, who finally can study Pinkie after her mentor arrives in Ponyville to retrieve her. Between the years of rock farming and her new life as a party planner, Pinkie was a martial artist, a brilliant disciple in the nuttiest and most powerful form of hoof-to-hoof combat, Shugakain. The time has come to recieve her final training, and she must spend three months on the poorest part of Equestria to train, kept company only by an overanalyzing Twilight and Spike, who seems to be losing his mind. As well as documenting her friend's tribulations, Twilight tries to piece together the broken memories Pinkie reveals as she sleeps.

Back home, madness strikes Ponyville. The remaining four Elements of Harmony enter a 2500 bit bet: whoever can go two months with their life turned upside down wins a fortune. And so it comes to pass that Rainbow Dash goes to college, Applejack becomes a romance writer, Rarity plays dress-up as a birthday party clown, and poor Fluttershy enters the ring as an amateur buckboxer... Will their friendship keep them bound together, or will a year's worth of tax free money be enough to split the four friends apart? What secrets lie buried in Pinkie's mind? And what happens when Twilight is finally proven right on a problem settled long ago?