The most common and most likely answer to this crossword clue is the 8 letter word CHAIRMAN
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More clues leading to the result CHAIRMAN
- Conservative shock with chap meeting leader
- What Prof. has, fellow who presides at meetings?
- Boss to carry player on a lap of honour?
- In revolutionary China, run by Mao, mostly as leader
- Check pilot who’s in charge on board
- Tea girl’s name for Mao?
- In march, a revolutionary leader like Mao?
- Check with pilot for person on board
- Officer locks maiden in jail
- Following check, expose piece, one on board
Buddy explains!

The straight part
We know that "one running the show" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one running the show = chairman.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 CHAIRMAN mean?
CHAIRMAN noun- A person presiding over a meeting.
- The head of a corporate or governmental board of directors, a committee, or other formal entity.
- Someone whose job is to carry people in a portable chair, sedan chair, or similar conveyance.
- To serve as chairman.