Bad actors ruined show (9)
I believe the answer is:
broadcast
'show' is the definition.
(broadcast is a kind of show)
'bad actors ruined' is the wordplay.
'ruined' indicates an anagram.
'bad'+'actors'='badactors'
'badactors' with letters rearranged gives 'BROADCAST'.
(Other definitions for broadcast that I've seen before include "distributed by hand" , "Transmit (programme)" , "Show" , "Put on the air" , "Transmit by radio or television" .)