Puzzle, urgent one I must crack (8)

I believe the answer is:

intrigue

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'must crack' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.

'puzzle urgent one i' is the wordplay.
'puzzle' indicates anagramming the letters.
'one' becomes 'i' (Roman numeral).
'urgent'+'i'+'i'='urgentii'
'urgentii' anagrammed gives 'INTRIGUE'.

Can you help me to learn more?

(Other definitions for intrigue that I've seen before include "pique?" , "An underhand plot or conspiracy" , "Mysterious quality" , "Rouse interest" , "Love-affair" .)

I've seen this clue in The Times.

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