The usually brooding Michael Shannon is terrifically funny as Felix Artifex, a second-rate theatrical producer defeated by the grandeur of his ambitions, in Craig Wright’s unevenly entertaining showbiz send-up. Alone onstage for most of the show, he’s always active: His eyes dart with fear behind black spectacles, and frantic hand gestures reflect his growing agitation. If only Wright’s play weren’t such a slog.—Diane Snyder