Story ultimately relayed in song (4)
I believe the answer is:
lied
'song' is the definition.
(type of German song)
'story ultimately relayed' is the wordplay.
'story' becomes 'lie' (story can mean a fabrication).
'ultimately' indicates one should take the final letters.
The final letter of 'relayed' is 'd'.
'lie'+'d'='LIED'
'in' is the link.
(Other definitions for lied that I've seen before include "Told fibs - German song" , "Told stories" , "Produced pork pie" , "Made up a story" , "Song in Berlin" .)