Settles in on Civil Service scene unhappily (9)

'settles' is the definition.
('ensconce' can be a synonym of 'settle')

'on civil service scene unhappily' is the wordplay.
I cannot really see how this works, but
'on' could be 'o' (I've seen this in other clues) and 'o' is present in the answer.
'scene' could be 'sc' (theatrical abbreviation) and 'sc' is found in the answer.
This may be the basis of clue (or it may be nonsense).

'in' is the link.

Can you help me to learn more?