Mount Vernon’s own professional opera company, Pacific Northwest Opera, presents “The Knight of the Rose” (Der Rosenkavalier ) starring Metropolitan opera soprano Katie van Kooten. This comic opera by Richard Strauss has some of the most sublime music ever written, suffused with the gaiety of Vienna with it’s sparkling waltzes and the spirit and grace of Mozart. Four performances: Friday April 14 7 pm, Sunday April 16 1:30 pm, Friday April 21 7 pm , Sunday April 23 1:30 pm.