For our series What’s That Building, a haunting story from a small Illinois town that’s puzzled people for nearly 150 years. Two young girls, one living and one long dead, and a mysterious connection that defied explanation. It’s known as the “Watseka Wonder” and it all happened just 80 miles south of Chicago. We’ll dig into the eerie events of 1878, when a supposed spirit possession captivated the nation and find out what’s become of the two homes where it all took place. For a full archive of In the Loop interviews, head over to wbez.org/intheloop.