Plug in the night before escape (5)
I believe the answer is:
evade
'escape' is the definition.
(I know that evade is a more specific form of the action escape)
'plug in the night before' is the wordplay.
'plug' becomes 'ad' (as in plugging a product).
'in the' means one lot of letters goes inside another.
'night before' becomes 'eve' (eve can mean the night before something).
'ad' going inside 'eve' is 'EVADE'.
(Other definitions for evade that I've seen before include "Dodge, duck" , "Avoid, get out of" , "Fail to pay" , "Dodge, elude" , "Dodge or equivocate" .)