Something sinister is brewing in the furthest corners of the world…

As Princess Twilight Sparkle begins to feel the pangs of divinity and faces the emotional and moral consequences of rejecting Flash Sentry, an unknown organization threatens the security of the newly allied Changeling Kingdom by sealing off the entirety of the changeling capitol city of Chitin with an unbreakable barrier of living, regenerating tissue. The still fresh-from-the-oven politician is soon tasked with traveling to the walled city to devise a solution with Dr. Seymour, an amateur biophysics professor from Canterlot with a distinctive ability to look deeper into situations than most others.

But when a swift epidemic devastates the city during their stay, Princess Celestia and Queen Chrysalis order an immanent contingency plan to sterilize the infection by leveling the capitol city- killing all non-infected citizens who do not leave by the declared execution time. Evacuation from the biohazard only proves more and more difficult after Twilight falls ill. Even with Seymour’s strong desire to return his new partner to the safety of Equestria, he may soon learn first-hand that some situations just can’t be forseen, and the ability to think on one’s hooves is one to be desired…