The whole crew may be bananas! (5)

I believe the answer is:

bunch

I'm a little stuck... Click here to teach me more about this clue!

'the whole crew' is the definition.
'bunch' can be an answer for 'crew' (synonyms). I'm unsure of the 'the whole' bit.

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for bunch that I've seen before include "Cluster (of grapes)" , "A cluster, group" , "Show silly fondness" , "Group of people (informal)" , "Group (of bananas)" .)

I've seen this clue in the Evening Standard.

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