Crossword Genius

Fantastic carolling can be arresting (9)

Ross

I believe the answer is:

collaring

'arresting' is the definition.
('collar' can be a synonym of 'arrest')

'fantastic carolling' is the wordplay.
'fantastic' indicates anagramming the letters.
'carolling' with letters rearranged gives 'COLLARING'.

'can be' is the link.

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