Unmatched interest, say, about detailed story (12)
I believe the answer is:
incomparable
'unmatched' is the definition.
(similar in meaning)
'interest say about detailed story' is the wordplay.
'interest say' becomes 'income' (I can't explain this - if you can you should believe this answer much more).
'about' means one lot of letters goes inside another.
'detailed' means to remove the last letter (the tail of the word is removed).
'story' becomes 'parable' (parable is a kind of story).
'parable' with its final letter taken off is 'parabl'.
'income' going around 'parabl' is 'INCOMPARABLE'.
Can you help me to learn more?
(Other definitions for incomparable that I've seen before include "Unrivalled" , "Unequalled" , "Second-to-none" , "Matchless" , "like no one else?" .)