And in the holds, working, are the experienced people (3,5)
I believe the answer is:
old hands
'the experienced people' is the definition.
(I've seen this in another clue)
'and in the holds working' is the wordplay.
'in' indicates putting letters inside.
'working' indicates anagramming the letters.
'holds' with letters rearranged gives 'oldhs'.
'and' placed within 'oldhs' is 'OLD HANDS'.
'are' acts as a link.
(Other definitions for old hands that I've seen before include "Experienced persons" , "Veterans" , "Experts" , "experienced types" , "Experienced people who have given long service" .)