A-listers got drunk during midweek (5)
I believe the answer is:
elite
'a-listers' is the definition.
(I've seen this in another clue)
'drunk during midweek' is the wordplay.
'drunk' becomes 'lit' (slang term).
'during' means one lot of letters goes inside another.
'midweek' becomes 'ee'.
'lit' put within 'ee' is 'ELITE'.
'got' acts as a link.
(Other definitions for elite that I've seen before include "A privileged or superior social group" , "Upper crust" , "Choice group" , "Creme de la creme" , "Group enjoying superior status" .)