They'd seen it in movies: every possible interpretation of the zombie apocalypse. Sometimes they walked, sometimes they ran, always they were deadly. But no one ever expected them to curse. In hindsight it shouldn’t have been at all surprising. It had been known for a while that the brain stores profanities differently from the rest of the rest of the language centre. There had been countless heartbreaking cases of patients recovering from a stroke and lost the power of speech. The joy of their loved ones when they started swearing, and the terrible disappointment when they realised that was the only thing they could say, was repeated thousands of times in hospitals everywhere.
Then in October of 2013, it happened to everyone. As predicted, the virus was quarantined, but it escaped through the air vents. By the time they discovered the extent of the spread, it had been incubated in the bodies of thousands with no visible symptoms. Once it spread to the brain however, their high level functions started to go. They began forgetting where they lived, and ambled around aimlessly. Their higher motor functions were the next to go, so the walking changed to a zombie-like amble. Finally they lost the power of speech, but for the primitively emotional part of their brains, which was still firing off at full pelt, reaching for the only words it knew how to say.
“Fuck fuck, shitting fuck.”
“What's wrong with John, he's gone mental.”
“Don't go near him. He's got that disease!”
“Why the fuck not?”
“Oh no... not you too!”
“What the fuck?”
“Shitting hell, shit shit fuck.”
“Wank you fucking bastard. Fucking cunt.”
And so it came to pass that the swearing hoard poured out of university halls on a Friday night and overran the city, making crude noises, overwhelming the transport system and damaging property.
But nothing had really changed after all.