Lad about to return stolen property (5)
I believe the answer is:
booty
'stolen property' is the definition.
(booty is a kind of stolen property)
'lad about to return' is the wordplay.
'lad' becomes 'boy' (I've seen this in another clue).
'about' indicates putting letters inside.
'return' shows that the letters should be reversed in order.
'to' reversed gives 'ot'.
'boy' enclosing 'ot' is 'BOOTY'.
(Other definitions for booty that I've seen before include "Money holder" , "Valuable stolen goods" , "Loot" , "Spoils" , "Ill-gotten gains" .)