If you think you know all about Batman and Gotham City, think again.=2 0While there may be someone running around in a cape making blockbuster movies this summer, you haven’t seen (or heard) anything yet if you haven’t gone on a nighttime bat expedition in Central Park with the real Batman and Batgirl of Gotham City, Bradley Klein and Daniellle Gustafson, who, in conjunction with the American Museum of Natural History give annual Bat Tours each summer. Both Mr. Klein and his wife, Ms. Gustafson, are founding members of the New York Bat Group and strong supporters of Bat Conservation International. Hear the real sonic clicks and calls of bats in the night as we talk to Mr. Klein, Ms. Gustafson, and a special guest, author Marie Winn of "Central Park in the Dark"