Caption missing from action-replay in film (5)

I believe the answer is:

layer

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'film' is the definition.
(thesaurus)

I don't understand the rest of the clue.

(Other definitions for layer that I've seen before include "Stratum or thickness" , "course" , "Stratum, tier" , "Hen, perhaps" , "Tier or thickness - or a hen?" .)

I've seen this clue in the Irish Times.

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