Directed to drop temperature? Get angry (3,3)

I believe the answer is:

see red

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'get angry' is the definition.
(synonyms)

I cannot understand how the rest of the clue works.

(Other definitions for see red that I've seen before include "lose control" , "get angry" , "Get furious" , "Grow furious" , "Become angry like bull" .)

I've seen this clue in The Times.

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