Lumpkin’s Big Top, New Millennium Theatre Company, at the Theatre Building Chicago. This annoyingly inept mediocrity is the ur-example of why playwrights should never direct their own scripts. Chicago writer Thurston Cobb religiously respects every imbecilic stereotype and blatant plot point in his relentlessly unfunny, egregiously repetitious “comedy,” an expose of a TV kids’ show threatened with replacement by computer animation. A real director would have cut the groaner antigags, sped up the leave-nothing-to-the-imagination dialogue, and eliminated the intermission. All that wouldn’t have rescued the show, but it would have minimized our exposure.

A fatal problem is the character of Lumpkin, supposedly America’s favorite clown but in fact an obnoxious alcoholic who takes the audience hostage in the second act (as if that hadn’t happened in the first). Loudly played by an irritating Ed Gass, he’s the underdog (not worth rooting for) in a messy battle with a bitchy corporate honcho, played by Leslie Kerrigan as a human dart board. Cobb throws in a clown who can’t juggle and Siamese triplets intent on breaking up their act, whose shenanigans are so predictable you want to make a citizen’s arrest.

The action is patently improbable; the potty, beaver, and Jesus jokes self-destruct; and the work’s 100 minutes seem like the Cretaceous era thanks to Cobb’s molasseslike pacing. Where are Krusty the Clown and Sideshow Bob when you need them?