If ever there was proof of the adage that what goes around comes around, it has been the recent fascination with the genius of Kurt Weill. Weill's music used to be associated mostly with classic interpretations by his wife Lotte Lenya or dark cabaret scenes from old Marlene Dietrich movies. Recent years have spawned a new group of interpreters, ranging from opera singer Julia Migenes to rock singer Sting, but none has made a more indelible impression than 26-year-old West German singer Ute Lemper. Lemper possesses not only the acting ability needed to pull off this dramatic music but also a formidable voice and a vast array of colors and moods at her disposal. She has helped redefine the stylistic performance boundaries of Weill's music and single-handedly restored a vitality and freshness to it. Lemper's appearance on the Allied Arts pops series will follow Weill's remarkable career chronologically, from his early German successes through his French period to his most popular American theater songs from the 40s. Lemper not only brings off all three languages and styles with considerable ease and conviction, but she also offers fascinating vignettes and anecdotes that make the man and the music all the more accessible. Tonight, 8 PM, Orchestra Hall, 220 S. Michigan; 435-6666 or 435-8122.