Security guards, a merchandise table, and a video of the cast strutting to the theater (a la Chris Martin in “Fix You”) create a rock vibe for this show by four improvisers. Setting a blistering pace in ever sharpening bits, they don’t milk jokes dry–they don’t even wait for them to register. Sometimes they seem preoccupied with just making one another break into giggles. That approach is risky, but with their comic savvy and dorky looks (Mort Burke’s moppy head is its own punch line), it works for them. “We’re willing to forsake art for fuckin’ around,” explains performer Brandon Sornberger. The trade-off for this kind of speed is inconsistency. If only their humor rocked out every scene. Open run: Fri midnight, I.O., 3541 N. Clark, 773-880-0199, $5.