THE SYSTEM OF DR. TARR AND PROF. FETHER (1844)

I'm surprised that this story has never been very popular in cinema and TV. Perhaps its "big reveal" would seem too obvious to many modern viewers, that of "the inmates running the asylum."

Another unnamed narrator chooses to take a tour of a modern asylum, and finds that all of the members of the staff, including director Monsieur Mallard, seem to act strangely at dinner. The narrator even notices that the people's clothes don't fit them well, but at no time does he tip to the solution. By chance the normal asylum-staff-- who have been tarred and feathered by the reigning lunatics-- manage to break free and re-take the madhouse, though the tarred-up employees look like "big black baboons from the Cape of Good Hope" to the befuddled narrator.

Doctor Tarr and Professor Fether are merely figments of Mallard's imagination, his joking reference to the torments he and his fellow nutcases have visited on the asylum-staff. By story's end the unusually thick narrator still thinks that the fictional authorities still exist, so maybe he's had his own mental breakdown.