Drop a soap opera (4)
I believe the answer is:
saga
'soap opera' is the definition.
(I've seen this before)
'drop a' is the wordplay.
'drop' becomes 'sag' (sagging is a kind of dropping**).
'sag'+'a'='SAGA'
(Other definitions for saga that I've seen before include "A long story or poem - it's a gas" , "Norse epic" , "A long adventurous story - it's a gas" , "Account of great heroism" , "Medieval Icelandic legend" .)