Extremely fast shot ultimately typifies finest Clooney show (8)
I believe the answer is:
screamer
'extremely fast shot' is the definition.
'screamer' can be an answer for 'shot' (I have seen 'powerful shot' mean 'screamer' so perhaps 'shot' could also mean 'screamer'). I am unsure of the 'extremely fast' bit.
'ultimately typifies finest clooney show' is the wordplay.
I cannot really understand how this works, but
'finest' could be 'cream' (the cream of something is its finest examples) and 'cream' is found within the answer.
'show' could be 'er' (US medical drama) and 'er' is found within the answer.
A single letter 's' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for screamer that I've seen before include "powerful shot" , "express delivery" , "she'll give voice" , "Sensational newspaper headline - mere scar (anag)" , "Remarkable thing; noisy person; large water bird" .)