In London, stop politician hiding in box (6)
I believe the answer is:
temple
'in london stop' is the definition.
(stop on the London Underground)
'politician hiding in box' is the wordplay.
'politician' becomes 'MP' (Member of Parliament).
'hiding in' indicates putting letters inside.
'box' becomes 'tele' (I've seen this in other clues).
'mp' going inside 'tele' is 'TEMPLE'.
(Other definitions for temple that I've seen before include "Side of head or holy building" , "Place of worship - side of the head" , "centre of interest?" , "London lawyers' church" , "House of prayer" .)