A ticketing page on the Chicago Humanities website says you can see Charlie on July 12 at 8:00pm. There are 720 seats available and tickets go for $35-50.
More than this I do not know, because the event doesn't seem to be mentioned anywhere else on their site, and Google turns up nothing else. If you're going to be in Chicago in July, though, you might want to make an enquiry and see what it's all about.