Sets about bizarre beings (6)

I believe the answer is:

begins

'sets about' is the definition.
('begin' can be a synonym of 'set about')

'bizarre beings' is the wordplay.
'bizarre' is an anagram indicator.
'beings' anagrammed gives 'BEGINS'.

(Other definitions for begins that I've seen before include "Starts" , "Makes a start" , "Commences" .)

I've seen this clue in the Evening Standard.

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