Event at home leads to murder (2,2)
I believe the answer is:
do in
'murder' is the definition.
('do in' can mean to kill)
'event at home' is the wordplay.
'event' becomes 'do' (do is a kind of event).
'at home' becomes 'in' ('I'm in' can mean 'I'm at home').
'do'+'in'='DO IN'
'leads to' acts as a link.
(Other definitions for do in that I've seen before include "Murder" , "Knock off" , "Get rid of" .)