Thus Ken performed (4)
I believe the answer is:
done
'performed' is the definition.
(done can mean performed or accomplished)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for done that I've seen before include "Tricked" , "This settled" , "Finished like node" , "This sort of thing is socially acceptable" , "Swindled" .)