If, like me, you tend to think of musicals as brainless trivialities, spend an hour watching musical director Kevin Stites rehearse his cast for Babes in Arms. Analyzing a Lorenz Hart lyric as though it were the densest of Shakespearean sonnets, he unearths myriad complexities in seemingly straightforward numbers like “I Wish I Were in Love Again” and “You Are So Fair.” And he communicates his revelations to the performers joyfully, without overlooking the slightest detail of their diction, phrasing, or acting. His brainpower should make each of the show’s glorious songs (among them “The Lady Is a Tramp,” “Where or When,” “Johnny One Note,” and “My Funny Valentine”) an exuberant intellectual workout. There’s not much Stites can do about the evening’s trivialities, however, since they’re part and parcel of the gossamer-thin book by Hart and Richard Rodgers (adapted by John Guare). The story–Long Island teens put on a variety show to avoid forced deportation to a local “work camp”–strains credulity at every turn. But since this is a concert performance, in which the actors carry their scripts and there are no sets, no one expects you to believe anything anyway. The big-name draws in this final installment of the “Ovations!” series are former Cheers star George Wendt and current Broadway sensation Alice Ripley, who can ham and belt respectively with the best of them. But I’d pay admission just to watch local nobody Rachel Rockwell, who has the kind of vocal sophistication and comedic panache that can make musical comedy such a delight. Auditorium Theatre, 50 E. Congress, 312-902-1500. May 18 through 21: Thursday-Saturday, 8 PM; Sunday, 3 PM. $17-$77. –Justin Hayford