Senior Karen Han (front) as Rosalia sings the praises of Puerto Rico in a rousing version of the crowd favorite "America" during Monday's dress rehearsal for "West Side Story." Shark girl Melissa Rosas, a subfreshman, is behind Han. The cast, crew, and orchestra are putting in five-hour rehearsals to get ready for opening night Thursday at 7 in the North Attic Playhouse. Tickets are almost gone for the show's four performances, which include 7:30 p.m. Friday and 2:30/7:30 p.m. Saturday. The spring musical is directed by Barbara Ridenour, with music direction by Rick Murphy. Kim Alexander and Alicia Cross-Engelhart are in charge of choreography.