Chicago has its share of murder mysteries throughout history, and its share of corruption. But there’s one story that seems to have been forgotten. One Spring day in 1889, a well-known Irish doctor named P.H. Cronin was found murdered and laying in a sewer. In the following weeks, Chicago erupted in both shock and fascination, and brought about a worldwide media frenzy. Dr. Cronin’s funeral procession was followed by four thousand mourners, the biggest funeral the city had seen since Abraham Lincoln’s. In her new book “Blood Runs Green,” author Gillian O’Brien tells the story of Irish Nationalism in Chicago in the late 1800’s, and how this murder affected it. She joins us in studio.