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Terrified hostages with a puzzle (5,2,1,5)

Ross

I believe the answer is:

white as a ghost

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'terrified' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.

'hostages with a puzzle' is the wordplay.
'puzzle' indicates an anagram.
'hostages'+'with'+'a'='hostageswitha'
'hostageswitha' is an anagram of 'WHITE AS A GHOST'.

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