Do what Mars and Pluto are thinking (9)

I believe the answer is:

disfigure

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'do what mars' is the definition.
I can't judge whether this defines the answer.

'pluto are thinking' is the wordplay.
'pluto' becomes 'dis' (another name for the mythical god).
'are thinking' becomes 'figure' (I can't justify this - if you can you should give a lot more credence to this answer).
'dis'+'figure'='DISFIGURE'

'and' acts as a link.

Can you help me to learn more?

(Another definition for disfigure that I've seen is " Deface".)

I've seen this clue in The Times.

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