Phrenzy, pH Productions, at Wing & Groove Theatre. This competitive improv show from new performance ensemble pH whittles down contestants in the reality-TV style that’s conquered the world. For the first five rounds, elimination is governed by the host, whose arbitrary rules are concealed from the cast but not the audience; after that things get more democratic–the players fall prey to audience whim. Throw in random “refereeing” (the host can make anybody sit out for just about anything, from dropping the ball to beating a dead horse to breathing the wrong way) and you’ve got a recipe for the most athletic idiocy you’ll find on a late-night stage in Chicago.

Some of the early-round rules were well conceived the night I attended, eliminating performers for employing classic crutches: variation-on-a-theme accents, playing children, stalling for time. Some of the freelance reffing was even better, punishing players for portrayals too hackneyed, heady, or close to home; host Kristine Kitts was given–and deserved–a big round of applause. The second half was less, well, fair; on the other hand, watching selfless-in-theory improv get ground down to its egomaniacal core is always a hoot.

None of this would work without a practiced, talented troupe–the gimmickry’s actually a serious drag on momentum, requiring about twice the energy of your average show. Fortunately this fresh-faced, giddy bunch delivers the goods. Nothing revolutionary, just a lot of whip-smart, hopped-up old school fun.