The most common and most likely answer to this crossword clue is the 4 plus 3 plus 2 plus 5 letter word COME OUT IN FORCE
C
O
M
E
O
U
T
I
N
F
O
R
C
E
Buddy explains!
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.