Beach alarm blocked by old unspecified people (2-3-3)
I believe the answer is:
so-and-sos
'unspecified people' is the definition.
(I've seen this in another clue)
'beach alarm blocked by old' is the wordplay.
'beach' becomes 'sands' (sands can mean a beach area).
'alarm' becomes 'os' (I can't justify this - if you can you should believe this answer much more).
'blocked by' indicates putting letters inside (I've seen this in other clues).
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'sands'+'os'='sandsos'
'sandsos' going around 'o' is 'SO-AND-SOS'.
Can you help me to learn more?
(Other definitions for so-and-sos that I've seen before include "Certain people" , "Unpleasant people who need not be named - thus and thus" , "Objectionable people thus and thus" .)