Somehow thinks wife cheated, invoking puzzled query (4,3,7)

I believe the answer is:

what the dickens

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'puzzled query' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'somehow thinks wife cheated' is the wordplay.
'somehow' indicates an anagram.
'wife' becomes 'w' (abbreviation).
'thinks'+'w'+'cheated'='thinkswcheated'
'thinkswcheated' is an anagram of 'WHAT THE DICKENS'.

'invoking' acts as a link.

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I've seen this clue in The Times.

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