Wave presenting no danger to the criminal (4-7)

'the criminal' is the definition.
Both the definition and answer are singular nouns.
Maybe they are linked in a way I don't understand?

'wave presenting no danger' is the wordplay.
I cannot quite see how this works, but
'wave' could be 'breaker' (breaker is a kind of wave) and 'breaker' is found within the answer.
The remaining letters 'safe' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).

'to' acts as a link.

Can you help me to learn more?