Firm screening premiere of network broadcast (4)
I believe the answer is:
sent
'broadcast' is the definition.
(I've seen this in other clues)
'firm screening premiere of network' is the wordplay.
'firm' becomes 'set' (I've seen this before).
'screening' indicates putting letters inside (I've seen this in other clues).
'premiere of' suggests taking the first letters.
The first letter of 'network' is 'n'.
'set' placed around 'n' is 'SENT'.
(Other definitions for sent that I've seen before include "Thrilled" , "Dispatched" , "Shipped" , "old money in Tallinn" , "Remitted" .)