Special Holtmann production; Detective (5-7,3)

I believe the answer is:

plain-clothes man

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'idetectivei' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'special holtmann production' is the wordplay.
'production' indicates an anagram.
'special'+'holtmann'='specialholtmann'
'specialholtmann' is an anagram of 'PLAIN CLOTHES MAN'.

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I've seen this clue in the Sydney Morning Herald.

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