The P-Pocalypse is The End (of the world as you knew it, anyway), the Day of the P-People, those strange creatures with interesting hats, crooked eyebrows, and an excess of snark. All those whose names Prominently featured a "P" were welcome in the soul-crushing attack on the masses, and they were led by the FourFour P's of the aPocalypse: P, as Pestilence; prettyeyes, as Death; and Percy McKean as Famine.
The apocalypse
These three were then supplemented by a fourth P in the form of the Professor, as Pollution, as well as Miselle Serafine as Pserafine, the ladies' auxiliary as Improper Use of Grammar, and Basil the Tired Aesthete as the Horticultural Battalion.