Inspector's son kidnapped by hideous crone (6)
I believe the answer is:
censor
'inspector's' is the definition.
(a censor inspects things)
'son kidnapped by hideous crone' is the wordplay.
'son' becomes 's' (genealogical abbreviation for son).
'kidnapped by' means one lot of letters goes inside another.
'hideous' is an anagram indicator (I've seen this in other clues).
'crone' anagrammed gives 'cenor'.
's' going into 'cenor' is 'CENSOR'.
(Other definitions for censor that I've seen before include "Blue-pencilling official" , "Official banner of books, films etc" , "Bowdlerise" , "Suppress anything considered obscene or politically unacceptable" , "Blue-pencil official" .)