Loud workmen I’d recast in radio play (5,4,4)
I believe the answer is:
under milk wood
'radio play' is the definition.
(I've seen this before)
'loud workmen i'd recast' is the wordplay.
'recast' indicates anagramming the letters.
'loud'+'workmen'+'id'='loudworkmenid'
'loudworkmenid' is an anagram of 'UNDER MILK WOOD'.
'in' acts as a link.
(Other definitions for under milk wood that I've seen before include "Welsh play" , "Radio play by Dylan Thomas" , "Fail fully to exploit deal" , "Radio poem by Dylan Thomas" , "Work by Dylan Thomas" .)