Idol with magic formula in musical (8)

I believe the answer is:

godspell

'musical' is the definition.
(1971 musical)

'idol with magic formula' is the wordplay.
'idol' becomes 'god' (synonyms).
'with' means one lot of letters go next to another.
'magic formula' becomes 'spell' (magic spell).
'god'+'spell'='GODSPELL'

'in' is the link.

(Another definition for godspell that I've seen is " Musical about Jesus Christ".)

I've seen this clue in The Telegraph.

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