As a sample of cutting-edge Moscow theater, Tverboul is rich. The songs by Alexey Paperny and Eugene Kadimsky are amalgams of Slavic pop, French accordion waltzes, and klesmer-style exuberance, while Eugene Arshanski's staging illustrates the text--performed in Russian--with viscerally accessible stage pictures. At once sardonic and celebratory, Tverboul is a musical portrait of life along the Tverskoi Boulevard, one of Moscow's busiest streets. Comparing the thoroughfare to a "broken contract," Tverboul attempts to capture the sinister, often illusory feeling of boundless freedom presented by the beckoning boulevard. These performances are being presented by the Chicago Actors Ensemble (which recently returned from a five-month tour of the now-misnamed Soviet Union), and they're part of the first U.S. visit by Moscows Comradeship of Actors and Musicians, a youthful troupe--its oldest member is 30--of 15 actors. (In the three years since they created Tverboul, they've won awards for it at both the Edinburgh Festival and a Soviet-arts festival in Kassel, Germany.) If nothing more, Tverboul should offer a core sample of the musical interests of young Soviets; its eclectic score mirrors the restlessness of a changing country. At the Chicago Actors Ensemble, July 8 through 10. Monday, 7 PM (followed by a benefit reception for the Chicago Actors Ensemble); Tuesday and Wednesday, 8 PM. July 8 tickets $20; other shows $10-$12.