Story in vacuous action or sci-fi film (5)
I believe the answer is:
alien
'sci-fi film' is the definition.
(1979 film)
'story in vacuous action' is the wordplay.
'story' becomes 'lie' (story can mean a fabrication).
'in' means one lot of letters goes inside another.
'vacuous' says to hollow out the word (remove centre letters).
'action' with its centre removed is 'an'.
'lie' placed within 'an' is 'ALIEN'.
'or' is the link.
(Other definitions for alien that I've seen before include "Creature from another planet" , "repugnant" , "Being from another world" , "Unfamiliar; foreign" , "Someone from outer space?" .)