How to Act, Wholesale/Chicago, at the Lunar Cabaret, through August 3. This high-concept performance piece almost defies description, which I think means it’s a success. You might call Jim Strahs’s non sequitur-sprinkled free-associative script a hybrid parody of overintense acting classes and one-man shows, as one mad teacher delivers a runaway “instructional” monologue. The evening’s best moments, however, are arresting bits of genuine artistry, especially a few songs that masterfully alloy mock and dead serious. And since star Michael Stumm–a former Wooster Group member–has taught acting for 20 years, it seems possible the whole thing might, in a hyperabstract way, be in earnest. But then there’s this sort of prompter-stage manager, occasionally supplying a monotone line from a three-ring binder, undercutting any pretense of sincerity. And then there’s the photos of ass decorating the stage…Though exceptionally smart, the text purposely hovers just this side of coherence, making for a studied vacancy that’s tantalizing or trying depending on your taste. Regardless, as prickly wiseassery goes, this is a lot of fun.

Bristling with practiced self-importance, Stumm is a commanding physical presence–one of those frustrating types who thinks he’s really, really special and is. Resembling nothing so much as a coked-up Dick Cavett, he offers shrilly hilarious theatrical demonstrations, sometimes trance-inducing impromptu songs, and mercifully crisp jogs through scattered bits of cheap slapstick. As his seriously low-energy sidekick, Marissa McKown personifies disinterested boredom and supplies crack backing vocals and instrumentation when needed. Directed by Stefan Brun.