True crime podcast's visionary (7)

I believe the answer is:

sincere

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'true' is the definition.
(associated in meaning)

'crime podcast's visionary' is the wordplay.
'crime' becomes 'sin'.
'podcast's visionary' becomes 'cere' (I can't explain this - if you can you should give a lot more credence to this answer).
'sin'+'cere'='SINCERE'

Can you help me to learn more?

(Other definitions for sincere that I've seen before include "natural?" , "Candid" , "Without deceit, genuine" , "Genuine; deceit-free" , "like informal correspondents?" .)

I've seen this clue in The Independent.

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