Buster Keaton missing on second shooting of scene! (6)
I believe the answer is:
retake
'second shooting of scene' is the definition.
(another take when filming)
'buster keaton missing on' is the wordplay.
I cannot really understand how this works, but
'on' could be 're' ('on' can be mean 'with reference to') and 're' is found within the answer.
The remaining letters 'take' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
(Other definitions for retake that I've seen before include "Capture once more" , "Second attempt" , "Further sitting of an exam" , "back for another shot" , "Sit (an exam) again" .)