Second City's 90th revue is a sharp-witted, skillfully performed set of satiric sketches about middle-of-the-road citizens pulled this way and that in an ever more polarized society. Actor-authors Daniel Bakkedahl, Brian Boland, Lisa Brooke, Liz Cackowski, Antoine McKay, and Jean Villepique form a crack team who work skillfully off one another--and off the audience in the evening's improvised segments and in the free improv sets that follow most shows. Vignettes range from a running gag about a hapless Cubs fan trying and failing to catch a ball to a fourth-grade pageant celebrating American forces' search for Iraqi weapons of mass destruction; other bits include a spoof of dinosaur wildlife specials, TV sports coverage digitally enhanced to exaggerate the violence, and a Moline political rally where Democrats pester a candidate with questions about personal problems--theirs, not hers. Under Joshua Funk's direction, the cast displays the delicious mix of crisp timing and spontaneity that's a hallmark of the very best improvisational theater. "I don't mean that you have to change lines every night, but you can't do it quite the same way every time," says Second City cofounder Paul Sills in Jeffrey Sweet's oral history of the company, Something Wonderful Right Away. "The work of creation is renewable, renewable, renewable." Doors Open on the Right proves his point. The Second City, 1616 N. Wells, Chicago, 312-337-3992 or 877-778-4707. Open run: Tuesdays-Thursdays, 8:30 PM; Fridays-Saturdays, 8 and 11 PM; Sundays, 8 PM. $17-$19.