Grander lie broadcast by chief villain (10)
I believe the answer is:
ringleader
'chief villain' is the definition.
(eg the ringleader of a scam)
'grander lie broadcast' is the wordplay.
'broadcast' indicates an anagram (letters scattered or cast around).
'grander'+'lie'='granderlie'
'granderlie' is an anagram of 'RINGLEADER'.
'by' is the link.
(Other definitions for ringleader that I've seen before include "Main villain" , "Chief troublemaker" , "brains" , "One heading up illicit activity" , "Chief mischief-maker" .)