Crooked men about to plot in an underground vault (8)

I believe the answer is:

entombed

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'in an underground vault' is the definition.
I can't judge whether this definition defines the answer.

'crooked men about to plot' is the wordplay.
'crooked' indicates an anagram (a crooked or disrupted version of the letters).
'about' indicates putting letters inside.
'plot' becomes 'bed' (a plot of land).
'men' anagrammed gives 'enm'.
'enm' going around 'to' is 'entom'.
'entom'+'bed'='ENTOMBED'

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(Other definitions for entombed that I've seen before include "in a grave situation" , "Placed in a burial chamber" .)

I've seen this clue in The Globe and Mail.

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