Defending the robbery at gunpoint (8-2)

'defending' is the definition.
Although both the answer and definition are present participle verbs, I don't understand how they can define each other.

'the robbery at gunpoint' is the wordplay.
I cannot quite see how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found in the answer.
'at' could be 'in' (synonymous in some cases - eg at school, in school) and 'in' is present in the answer.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?