Succinct, putting the French prisoner in charge (7)
I believe the answer is:
laconic
'succinct' is the definition.
(thesaurus)
'the french prisoner in charge' is the wordplay.
'the french' becomes 'la'.
'prisoner' becomes 'con' (abbreviation for 'convict').
'in charge' becomes 'ic'.
'la'+'con'+'ic'='LACONIC'
'putting' is the link.
(Other definitions for laconic that I've seen before include "Concise - terse" , "with little expression" , "Terse; pithy" , "Terse - can coil (anag)" , "Col Cain (anag) - expressed in a few words" .)