Cryptic crossword clue
Difficult task catching foe masquerading as insider 3,2,2

The most common and most likely answer to this crossword clue is the 3 plus 2 plus 2 letter word ONE OF US

O
N
E
O
F
U
S

Buddy explains!

The straight part
We know that "insider /" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case insider / = one of us.
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.

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