Shenanigans -- performing after international gets into medals (6-2)
I believe the answer is:
goings-on
'shenanigans' is the definition.
'performing after international gets into medals' is the wordplay.
'performing' becomes 'on' (I've seen this in other clues).
'after' means one lot of letters go next to another.
'international' becomes 'i' (abbreviation eg in IMF).
'gets into' indicates putting letters inside.
'medals' becomes 'gongs'.
'i' inserted into 'gongs' is 'goings'.
'on' put after 'goings' is 'GOINGS-ON'.
(Other definitions for goings-on that I've seen before include "Activities, esp. dubious ones" , "mischief" , "Suspect events or behaviour" , "Suspicious happenings" , "Funny business" .)