Villainy that goes on at night? (4,5)

'villainy that' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'on at night?' is the wordplay.
'on' means one lot of letters go next to another.
'at' becomes 'deeds' (I can't explain this - if you can you should give a lot more credence to this answer).
'night?' becomes 'dark' ('dark' can be a synonym of 'night').
'deeds' after 'dark' is 'DARK DEEDS'.

'goes' is the link.

Can you help me to learn more?