Old story from Lille gendarme (6)
I believe the answer is:
legend
'old story' is the definition.
'legend' can be an answer for 'story' (legend is a kind of story). I am not certain of the 'old' bit.
'from lille gendarme' is the wordplay.
'from' indicates the answer is hidden within the clue.
'LEGEND' is hidden in the letters of 'lille gendarme'.
Can you help me to learn more?
(Other definitions for legend that I've seen before include "Caption; very well known" , "Very famous member's death" , "Footnote" , "hero" , "Old tale" .)