Rent dockland garage in secret (5-3-6)
I believe the answer is:
cloak-and-dagger
'secret' is the definition.
(I've seen this before)
'rent dockland garage' is the wordplay.
'rent' indicates an anagram (rent can mean torn or damaged).
'dockland'+'garage'='docklandgarage'
'docklandgarage' is an anagram of 'CLOAK-AND-DAGGER'.
'in' is the link.
(Other definitions for cloak-and-dagger that I've seen before include "underground" , "Concerned with intrigue and espionage" , "Involving intrigue and secrecy" .)