Lights not working inside of hall (5)
I believe the answer is:
offal
'lights' is the definition.
(I've seen this before)
'not working inside of hall' is the wordplay.
'not working' becomes 'off' (I've seen this before).
'inside of' says to take the centre.
The centre of 'hall' is 'al'.
'off'+'al'='OFFAL'
(Other definitions for offal that I've seen before include "Internal organs of an animal used as food" , "Internal organs and entrails as food" , "Bits of waste meat" , "Edible insides" , "Waste parts of a carcass" .)