Story finished, go to bed (3,2)
I believe the answer is:
lie up
'to bed' is the definition.
Both the answer and definition are verbs in their base form.
Perhaps you can see an association between them that I don't see?
'story finished' is the wordplay.
'story' becomes 'lie' (story can mean a fabrication).
'finished' becomes 'up' (eg 'time's up' means the time is finished).
'lie'+'up'='LIE UP'
'go' acts as a link.
Can you help me to learn more?
(Other definitions for lie up that I've seen before include "Berth" , "(Of ship) go into dock" , "Stay in bed" , "out of commission" .)