Be in shock and look upset (4)
I believe the answer is:
reel
'be in shock' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'look upset' is the wordplay.
'look' becomes 'leer' (leer is a kind of look).
'upset' shows that the letters should be reversed in order.
'leer' reversed gives 'REEL'.
'and' acts as a link.
Can you help me to learn more?
(Other definitions for reel that I've seen before include "Lurch; spool" , "Dance; winding drum" , "Stagger with rod winder" , "Dance - sway - cotton holder" , "Photographer's and anglers spool" .)