Anton Chekhov invented the modern short story, which reveals characters’ lives through discrete but telling episodes. In the masterful 1892 “Ward 6,” he turned his gaze on the well-meaning but criminally negligent director of a mental hospital, Dr. Ragin. Convinced that truth lies only in the mind and that physical suffering is illusory, the doctor devotes himself to a brainy paranoid, Gromov, thereby putting his career in jeopardy. Adapter-director Joe Feliciano’s somber, methodical staging for Mom and Dad Productions is aptly formal and restrained, and a poignant Chekhovian humanity emerges whenever Feliciano holds court as Gromov. But hesitant performances and an unwavering gloom obscure many of Chekhov’s meticulous details and hence the lives they should reveal. Through 10/9: Fri-Sun 8 PM. Heartland Studio Theater, 7016 N. Glenwood, 773-306-6595. $5-$15.