Sinister mastermind (8)

I believe the answer is:

svengali

(Other definitions for svengali that I've seen before include "Person who controls another's mind - musician and evil genius (created by George du Maurier)" , "Evil hypnotist in the George du Maurier novel, Trilby" , "someone having 5 [INFLUENCED] victims?" , "in novel form" , "man of influence" .)

I've seen this clue in The Times.

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