British soldier turns up and is in charge of conceited people (8)
I believe the answer is:
bigheads
'conceited people' is the definition.
(I've seen this before)
'british soldier turns up and is in charge of' is the wordplay.
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'soldier' becomes 'GI' (term for US soldier).
'turns up' is a reversal indicator.
'and' means one lot of letters go next to another.
'is in charge of' becomes 'heads' (I've seen this in another clue).
'gi' written backwards gives 'ig'.
'b'+'ig'+'heads'='BIGHEADS'
(Other definitions for bigheads that I've seen before include "Egotists" , "Conceited people" .)