1Across, Loutish behaviour of one with mullet perhaps on head(10)
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11 Across, Insect might escape(6) SORRY NO LETTERS
15 Across, Name often found in nightclub eagerly anticipating Oscar(1,4)
A ???I
18 Across, Change engulfing city institution,one notwithstanding being split up
(3-6) ??L-?E???R