The most common and most likely answer to this crossword clue is the 4 plus 5 letter word LOAN SHARK
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More clues leading to the result LOAN SHARK
- He takes an arm and a leg, like one who terrorised Amity Island, reportedly
- Pay attention after hearing only son becomes disreputable businessman
- Applying Koran, lash usurer
- See a new hotel in island – disreputable source of money?
- Financial dealer needing pounds has krona converted
- He takes a great deal of interest in report of solitary predator
- Karl has no trouble with person of enormous interest
- Noah's acting in play as Shylock, say
- Look, listen, comprehend answer for an usurer
- Following advances, hear from usurer
Buddy explains!

The straight part
We know that "person of enormous interest" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case person of enormous interest = loan shark.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.