The plucky Chicago Opera Theater begins its first season in its new Millennium Park space, the 1,400-seat Harris Theater, with Monteverdi's L'incoronazione di Poppea, the fourth COT collaboration between conductor Jane Glover and director Diane Paulus. Glover and Paulus worked together last season on the Benjamin Britten adaptation of Henry James's The Turn of the Screw, displaying the kind of attention to dramatic storytelling that's become a COT hallmark. Poppea tells the tale of a love triangle between the emperor of Rome, Nerone (Michael Maniaci), his mistress, Poppea (Danielle de Niese), and her previous suitor, Ottone (Tobias Cole). (It's actually more like a love pentagon, once you include Ottone's new sweetheart and Nerone's wife.) This tangle of corruption and betrayal not only gives rise to a murder plot against the philosopher Seneca, Nerone's adviser, but ends with the viciously ambitious Poppea crowned empress (hence the title). No complete manuscript of the score exists, so conductors usually adapt the music for a lineup of their own choosing; Glover has assembled a small period-instrument ensemble and a roster of singers that includes several COT veterans: soprano Kelli Harrington returns from last year's Brundibar, soprano Kara Shay Thomson was in The Turn of the Screw, and boy soprano Adam Benkendorf sang in both. These days the role of Nerone is usually sung by a woman, but Maniaci is a bona fide adult male soprano, such a rarity in the postcastrati era that he'll be the first I've ever heard in the flesh. The staging will be updated to the present, with modern dress--a tactic well suited to this historical drama of flawed leaders, messy intrigue, and political assassination (not to mention assignation). In Italian with English supertitles. Wednesday and Friday, February 18 and 20, 7:30 PM, Sunday, February 22, 3 PM, and Thursday and Saturday, February 26 and 28, 7:30 PM, Harris Theater, 205 E. Randolph; 312-704-8420, ext. 10.