Much Ado About Nothing, Act I — amuse patron afresh (1,5,2,1,6)
I believe the answer is:
a storm in a teacup
'much ado about nothing' is the definition.
(I've seen this before)
'act i amuse patron afresh' is the wordplay.
'afresh' indicates an anagram.
'act'+'i'+'amuse'+'patron'='actiamusepatron'
'actiamusepatron' anagrammed gives 'A STORM IN A TEACUP'.
(Other definitions for a storm in a teacup that I've seen before include "Much Ado about Nothing" , "too much for a trifle" .)