Set lines at end of episode (7)
I believe the answer is:
scenery
'episode' is the definition.
(I've seen this before)
'set lines at end of' is the wordplay.
'set' becomes 'scene' (scene is a kind of set).
'lines' becomes 'ry' (abbreviation for railway).
'at end of' is a charade indicator (letters next to each other) (some letters go at the end of others).
'scene'+'ry'='SCENERY'
(Other definitions for scenery that I've seen before include "Stage background" , "On-stage background" , "view in the country" , "flats" , "movie sets?" .)