I wonder is there a Mandarin term for " jump the shark" https://en.wikipedia.org/wiki/Jumping_the_shark which means the decline of quality of a T.V show reached the breaking point for the viewers, even the most loyal fans have no choice but give up on the show.
My guess would be 沒救了，
The T.V show 'House' finally jumped the shark. (電視劇 「醫神」終於沒救了。)
but is there other choices?
I am a native Cantonese speaker, there might be some mainland term I am not aware of.