Box female soldiers, with police car outside (7)
I believe the answer is:
pandora
'box female' is the definition.
(reference to the Pandora's box story)
'soldiers with police car outside' is the wordplay.
'soldiers with' becomes 'or' (Other Rank. I am not sure about the 'with' bit.**).
'police car' becomes 'panda' (I've seen this before).
'outside' is an insertion indicator.
'or' going into 'panda' is 'PANDORA'.
(Other definitions for pandora that I've seen before include "First mortal woman of Greek mythology" , "Possessor of famous box" , "Her box was filled with all the ills of the world" , "disobedient opener who might have helped 16" , "Girl with box of troubles" .)