When Celestia vanishes, everypony but Twilight Sparkle is turned into a vampire. She fights to survive in the ruin of Canterlot, until she's forced to leave. In the country town of Ponyville, a surprise awaits that will shatter her worldview forever.
When aliens came, they didn't come from Tartarus, like the ponies were expecting, but from under the sea, and magic couldn't stop them. Luckily our little ponies know something that can: Jaegers. They'll fight to stop The End, and they won't give up.