Illustrate long story between covers in digest (6)
I believe the answer is:
depict
'illustrate' is the definition.
(I know that depict is the is a more specific form of the action of illustrate.)
'long story between covers in digest' is the wordplay.
'long story' becomes 'epic' (eg an epic poem).
'between' is an insertion indicator.
'covers in digest' becomes 'dt' (I can't explain this - if you can you should give a lot more credence to this answer).
'epic' going inside 'dt' is 'DEPICT'.
Can you help me to learn more?
(Other definitions for depict that I've seen before include "Delineate" , "'Show, portray (6)'" , "Illustrate, describe in detail" , "Draw, describe" , "Portray, represent" .)