Old guides upset over shows (4)
I believe the answer is:
used
'old' is the definition.
(as in used or second-hand items)
'guides upset over shows' is the wordplay.
'shows' indicates a hidden word.
'over' says the letters should be written in reverse.
'desu' can be found hidden inside 'guides upset'.
'desu' in reverse letter order is 'USED'.
(Other definitions for used that I've seen before include "Enjoyed" , "Dog-eared" , "Dues (anag.)" , "cast off" , "That's not new" .)