Help a character in opera (4)

I believe the answer is:

aida

'opera' is the definition.
(Aida is an opera by Giuseppe Verdi)

'help a character' is the wordplay.
'help' becomes 'aid' (synonyms).
'a character' becomes 'a'.
'aid'+'a'='AIDA'

'in' is the link.

(Other definitions for aida that I've seen before include "Verdi's opera set in ancient Egypt" , "title role" , "she dies entombed" , "Princess" , "Verdi opera" .)

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

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