With its relentless punishing of the arrogance of power, this is truly a play without pity. Lear dooms himself when he splits his kingdom among his daughters, triggering a civil war. Even more powerful than the plot is the Bard's poetry, a scorching mix of hideous curses and hard-earned knowledge. Vitalist Theatre's three-hour modern-dress treatment is as energetic as it is eloquent, a gift from a cast who, as directed by Elizabeth Carlin Metz, know exactly who their characters are, how they differ, what they're saying, and why. Though not old enough to earn the full measure of pity, Don Bender as Lear is as honest in the anger he inflicts on himself as in the easier rage against those who betray him. Though there are many standouts, Lori Myers wins the bravura award for delivering both an affecting Cordelia and a supple Fool. Through 10/24: Thu-Sat 7:300 PM; Sun 2:30 PM. Theatre Building Chicago, 1225 W. Belmont, 773-327-5252. $22.