Very notable time period inspiring each TV serial (4,5)
I believe the answer is:
soap opera
'tv serial' is the definition.
(I've seen this before)
'very notable time period inspiring each' is the wordplay.
'very' becomes 'so' (both can mean 'extremely').
'notable time period' becomes 'era' (I've seen this in another clue).
'inspiring' is an insertion indicator.
'each' becomes 'apop' (eg 'one pound a pop' can mean 'one pound each').
'so'+'era'='soera'
'soera' placed around 'apop' is 'SOAP-OPERA'.
(Other definitions for soap opera that I've seen before include "TV serial such as Coronation Street" , "TV show" , "Serialised domestic melodrama on TV or radio" , "Sentimental TV serial, sounds clean" , ""Coronation Street", for example" .)