There are no people like show people—at least that’s what show people think. Look at all of the musicals they’ve made about themselves: Gypsy, 42nd Street, Singin’ in the Rain, Annie Get Your Gun. And who can blame them? By its nature show business is—well—showy, providing a home for people who are dramatic, provocative, and flamboyant.

Or almost nothing. Cy Coleman’s score can feel a bit old-fashioned, but two of the show’s most memorable songs—”There Is a Sucker Born Ev’ry Minute” and “The Prince of Humbug”—perfectly re-create the giddiness of a rousing circus march. The music conveys something essential about Barnum, his wild flimflammery and, in quieter moments, the man behind the bunk.

But Bramble’s Barnum doesn’t change. Oh, some things make him sad: His museum burns down, for instance. He leaves his wife to have an affair with Jenny Lind and then returns to her when it’s over. She hardly seems bothered by the dalliance. The show must go on.

Through 6/16: Wed 7:30 PM, Thu 2 and 7:30 PM, Fri 8 PM, Sat 2 and 8 PM, Sun 2 PM, Mercury Theater, 3745 N. Southport, 773-325-1700, mercurytheaterchicago.com, $25-$59.