Tosca is Puccini's "shabby little shocker'' (in the words of musicologist Joseph Kerman), and its gritty melodrama lends itself well to the realism of film. One celebrated screen version was filmed in Rome and starred Raina Kabaivanska as Tosca, Placido Domingo as Cavaradossi and Sherrill Milnes, shown here, as Scarpia. Opera Tampa is giving a free showing of this 1976 Tosca to introduce Milnes as the company's new artistic adviser and his wife, Maria Zouves, as its new associate director. Milnes will talk about the making of the movie, and there will be a tribute to the late Beverly Sills. The event is at 7 tonight in the TECO Theater of the Tampa Bay Performing Arts Center. (813) 222-4880.