Despite what this demure photograph tries to lead her to believe, Ms. Day suspects the talented Arianna String Quartet is actually a group of international party boys who really know how to let loose. She even thinks that under these tailored suits and pressed shirts they're all wearing tie-dyed T-shirts and Garfield boxer shorts  now that's wild! Join Ms. Day at 7:30 p.m. at the Sheldon Concert Hall (3648 Washington Boulevard) as she does a little investigating at the quartet's concert, which includes possible absinthe-guzzling anthems by Mozart, Respighi and Brahms. Tickets for this University of Missouri-St. Louis Premiere Performance (www.premiereperformances.org) cost $18 to $23 at 314-516-5818, but watching the cellist sign Ms. Day's, ahem, program after the show will be well worth that ticket price.