Total chaos, prime minister once was on edge (6)
I believe the answer is:
mayhem
'total chaos' is the definition.
(I've seen this before)
'prime minister once was on edge' is the wordplay.
I cannot quite see how this works, but
'edge' could be 'hem' (I've seen this before) and 'hem' is found in the answer.
'prime minister' could be 'may' (I've seen this in other clues) and 'may' is located in the answer.
No letters remain.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for mayhem that I've seen before include "State of great confusion and disorder" , "Big trouble!" , "Violent or damaging action, a crime" , "violence" , "Chaos, violent disorder" .)