Two years ago Mark Morris’s company finally introduced Chicagoans to his breakthrough 1988 work, L’Allegro, il Penseroso ed il Moderato, set to an oratorio by Handel. Now they return with a program premiered in 2006, Mozart Dances, described by Joan Acocella in the New Yorker as “the most grave and lovely piece Morris has made in years.” She adds, “In performance it is an utter thrill.” Mozart Dances consists of three pieces–“Eleven,” “Double,” and “Twenty-Seven”–each set to a different Mozart work: Piano Concerto no. 11, the Sonata in D Major for Two Pianos, and Piano Concerto no. 27. (Here the music will be performed by Music of the Baroque and pianists Ursula Oppens and Amy Dissanayake.) Expect, as usual with Morris, a gorgeous but down-to-earth response to the music; in Acocella’s words, “Though he may not have a story on the surface, he always has one underneath, in the form of movement motifs.” In fact he told her she’d misinterpreted the final moments of the final work, which were meant to recall the ambiguous ending of Cosi Fan Tutte. a Through 8/26: Fri 8 PM, Sat 7:30 PM, Sun 2 PM, Harris Theater for Music and Dance, 205 E. Randolph, 847-266-5100 or 312-334-7777, $30-$75. –Laura Molzahn