Crossword Genius

Withdrawn crowd nervily braces against this? (4,5)

Ross

I believe the answer is:

bomb scare

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

'against this?' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'withdrawn crowd nervily braces' is the wordplay.
I cannot really understand how this works, but
'crowd' could be 'm' and 'm' is found within the answer.
an anagram of 'braces' is 'bscare' which is located in the answer.
The remaining letters 'bo' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.
Want a hint initially instead of a full solution? Install my app