The most common and most likely answer to this crossword clue is the 11 letter word RINGLEADERS
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The straight part
We know that "chief troublemakers" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case chief troublemakers = ringleaders.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.
What does RINGLEADERS mean?
RINGLEADERS noun- A leader of a group of people, especially an unofficial group.
- A person who starts and leads a disturbance (such as a riot), a conspiracy, or a criminal gang.