A man wakes up one day in a world almost exactly the same as ours - but all the n's and m's are reversed. In this world, Dicken's most famous book is about cutlery, Mamma Mia is totally ruined, and 'anemone' is routinely mispronounced so that most people actually say the word correctly. It drives him mad. Which is to say, nad. As a final insult, the doctors pronounce hin imsame amd innure hin im a nadhouse.
In order to stave off the creeping despair at being stuck in an asylun in what is plainly the most ridiculous of all possible worlds, he begins to compile a dictionary of mn-less words. From that dictionary he embarks on a memoir (which he can confidently call an autobiography) that he secretly hopes will build a door back into the world he knew. He works on it for months, scribbling away into the night, carefully avoiding every alphabetically offensive word. Finally he reaches the end, but on the very last page he screws up and writes "THE EMD" in huge caps. "Danmit!" he shouts, but his book becomes a bestselling fantasy novel after the publisher puts a picture of a woman in a metal bikini on the cover.