Composure shown by model again (6)
I believe the answer is:
repose
I believe this clue is a double definition.
'composure' is the first definition.
(repose is a kind of composure)
'model again' is the second definition.
('pose' can be a synonym for 'model' so perhaps 'repose' is OK for 'model again')
'shown by' is the link.
(Other definitions for repose that I've seen before include "State of tranquillity" , "take it easy" , "calm" , "peace" , "Relaxation" .)