Note how mugshots break up; but we can’t stop now (3,4,4,2,2)
I believe the answer is:
the show must go on
'we can't stop now' is the definition.
I don't know anything about this answer so I cannot tell whether this works.
'note how mugshots break up' is the wordplay.
'break up' is an anagram indicator.
'note'+'how'+'mugshots'='notehowmugshots'
'notehowmugshots' is an anagram of 'THE SHOW MUST GO ON'.
'but' is the link.
Can you help me to learn more?
(Other definitions for the show must go on that I've seen before include "Send in the Clowns" , "trouper's philosophy" .)