Foreign story in article (5)
I believe the answer is:
alien
'foreign' is the definition.
(synonyms)
'story in article' is the wordplay.
'story' becomes 'lie' (story can mean a fabrication).
'in' means one lot of letters goes inside another.
'article' becomes 'an' (indefinite article).
'lie' inserted into 'an' is 'ALIEN'.
(Other definitions for alien that I've seen before include "of foreigners" , "Otherworldly" , "Stranger" , "Unfamiliar; foreign" , "repugnant" .)