I star in a moving production (5)

I believe the answer is:

astir

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'moving production' is the definition.
'astir' can be an answer for 'moving' (I've seen this before). I am unsure of the 'production' bit.

'i star' is the wordplay.
'i star' anagrams to 'ASTIR'.
However, I am unsure how the anagram is indicated.

'in a' is the link.

Can you help me to learn more?

(Other definitions for astir that I've seen before include "Up and about -- is art (anag)" , "abroad" , "Busy" , "Moving; out of bed" , "Excitedly moving" .)

I've seen this clue in The Globe and Mail.

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