Like Harold Pinter, to whom he's sometimes compared, David Mamet is a poet who happens to write plays, and any actor who ignores Mamet's rhythms does so at his peril. Last season the American Theater Company produced Mamet's American Buffalo--about a trio of losers scheming to rob a neighbor--and the production sagged. In the current revival the key role of Donny is taken by Chicago veteran Mike Nussbaum, who played Teach in the 1975 premiere. He clearly knows how to deliver Mamet's staccato dialogue, and he speaks with authority and power, setting the tone and pace for this savage, intense production. Donny is usually played as a middle-aged man filled with resentment, twisted with thwarted desire and free-floating anger. Nussbaum's Donny is a generation older and much more beaten down, though he refuses to admit defeat. Every line he speaks is packed with the urgency and desperation of a man fighting against the realization that life is never going to get any better. Andrew Micheli and John Sterchi, who both appeared in last year's revival, wisely follow Nussbaum's lead, turning in passionate, convincing, and committed performances. American Theater Company, 1909 W. Byron, 773-929-1031. Through July 29: Wednesdays-Saturdays, 8 PM; Sundays 3 PM. $25-$30.