Histrionics about a group (4)
I believe the answer is:
trio
'a group' is the definition.
The answer is an example.
'histrionics about' is the wordplay.
'about' indicates a hidden word (the clue goes around or about the answer).
'TRIO' is hidden in the letters of 'histrionics'.
(Other definitions for trio that I've seen before include "Threesome" , "Beethoven's 'Archduke', for example" , "Three of a kind" , "A group or set of three" , "Riot (anag)" .)