Insiders made money in jazz age Fitzgerald novel (4)
I believe the answer is:
emma
'novel' is the definition.
(novel by Jane Austen)
I don't understand the rest of the clue.
(Other definitions for emma that I've seen before include "Titled heroine" , "Jane Austen heroine" , "heroine of novel" , "J Austen novel" , "Retired chief in Ian Fleming" .)