Tonight and next Wednesday, July 23, locals Eastern Blok will play their fluid and vivid Balkan-inspired jazz at Katerina's, 1920 W. Irving Park, following screenings of films by the great Serbian director Emir Kusturica. Tonight it's the riotous tragic farce Underground--the movie that introduced many Americans to the astounding brass-band music of Boban Markovic, whose orchestra plays around town five times this weekend--and next week it's Black Cat, White Cat. Both nights the films play at 7 (sorry for the late notice!) and the music starts at 10. Cover is $8, and the bar's offering slivovitz drink specials for an authentic Balkan buzz.