Classic drama repeats showing an impossibility

I believe the answer is:

nono

I'm a little stuck... Click here to teach me more about this clue!

(Other definitions for nono that I've seen before include "Something that must not be done (informal)" , "Something not acceptaable" , "Non-starter (colloq.)" , "Unacceptable thing" , "Impossibility" .)

I've seen this clue in The Telegraph.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.