Sublimely silly and unashamedly offensive, Mel Brooks's musical skewers showbiz cliches while it celebrates Broadway's glorious excess with an anthology of shtick. The songs sell the story and the story sells the songs. Marc Robin's lean and hungry yet faithful staging reinvents Brooks's irreverence at every turn. The lovable title shysters are played by Chicago clown princes Ross Lehman and Guy Adkins, the former scheming up a storm, the latter sweetly needy, with an adenoidal warble and a late-blooming lust for life. They break up the audience more than they do each other, and Robin backs them with ironclad comic casting of a retinue of showbiz freaks. Make no mistake, the musical belongs to 1968, but laughter never dates. --Lawrence Bommer a Through 12/2: Wed 1 and 8 PM, Thu-Fri 8 PM, Sat 5 and 8:30 PM, Sun 1 and 5 PM, Marriott Theatre in Lincolnshire, Rte. 21 (Milwaukee Ave.), Lincolnshire, 847-634-0200, $45, dinner-show packages available.