The commotion when going to a party! (3)
I believe the answer is:
ado
'the commotion' is the definition.
(ado is a kind of commotion)
'going to a party' is the wordplay.
'going to' is a charade indicator (letters next to each other).
'party' becomes 'do' (do is a kind of party).
'a' next to 'do' is 'ADO'.
'when' acts as a link.
(Other definitions for ado that I've seen before include "Hoo-ha" , "Fuss, difficulty" , "Shakespeare: 'Much ... About Nothing'(3) ()" , "Flurry" , "Fuss, trouble" .)