Story or scene of happy innocence (5)
I believe the answer is:
idyll
I believe this clue is a double definition.
'story' is the first definition.
(I have seen 'Pastoral story ' mean 'idyll' so perhaps 'story' could also mean 'idyll')
'scene of happy innocence' is the second definition.
(I've seen this before)
(Other definitions for idyll that I've seen before include "paradise" , "Poem - charming scene" , "Happy peaceful scene" , "Romantic poem or scene" , "Simple story" .)