This enterprising group has put together a triple bill of early 20th-century operatic one-acts that unveils three disparate faces of love: the essential loneliness of the human soul, ardor cooled by deception and jealousy, and ironic bemusement. Yet all three derive their narrative drive from the discovery of a secret. In Bartok's Bluebeard's Castle (1911), loosely based an the fairy tale celebrated for its macabre denouement, the redemptive power of a woman is shattered by fatal curiosity. Puccini's Il tabarro ("The Cloak"), the first panel from his 1918 Triptych, shocks with its bloody climax. Susanna's Secret (1909) by Ermanno Wolf-Ferrari, on the other hand, is neither dark nor serious. Of the three scores, Bartok's is the most ambitious, psychologically probing, and intense as it contrasts Bluebeard's gloomy solitude with his new wife's insistent inquisitiveness. The Puccini is vintage verismo. And Wolf-Ferrari's music for his romantic comedy about a stealthy smoker is delectable. The relatively light orchestration and the brevity of these operas seem ideal for COC, which stages its productions (often ingeniously) in a cramped space and relies on a perky ten-piece ensemble (conducted by Lawrence Rapchak) for accompaniment. Several of the singers are capable of vivid performances. Bluebeard's Castle should be especially worthwhile, with bass-baritone Peter Van De Graaff in the title role and mezzo-soprano Julia Bentley as Judith, wife number four. Other soloists include Richard Alderson, Beverly Thiele, Leslie Casson, and Mark James Meier. Carl Ratner is the stage director. All of the works will be sung in English. Saturday, 7:30 PM, Sunday, 3 PM, and four more performances through May at the Ruth Page Theatre, 1016 N. Dearborn; 822-0770.