It was the end of a Chicago era. Antonio "Tony Napoli" Sorrentino has finally closed his legendary restaurant in the heart of the West Loop. It has been a gathering place for prominent politicians, famous entertainers, renowned dignitaries, and, of course, well-known mobsters. Often dubbed the "Artie Bucco" of the Chicago Outfit, 87-year-old Tony Sorrentino has decided to close his celebrated restaurant after 57 years. Suffering from late-stage cancer, the time had come to sell his property to a local developer and close his business for good. The demolition equipment arrived to begin annihilating his prominent restaurant one November afternoon. As Sorrentino sat in his Cadillac across the street, he uttered the words that so many FBI agents often wondered out loud: “If ‘dem walls could only talk.”

Suddenly, the demolition stopped, and several construction workers climbed out of their machines to begin digging through the rubble by hand. They abruptly make a gruesome discovery: Four decomposed bodies in large black body bags are discovered beneath the concrete foundation.

Chicago P.D. Detective Dennis Romanowski is very familiar with the famous restauranteur. Being half Italian, Sorrentino is a cousin on his maternal side, and has often referred to him as "Zio Tony". When called at the 18th District on that autumn day, he visits Sorrentino in his prison cell. There, he finds a sickly, broken old man being held on suspicion of first-degree murder. Realizing he may soon die in prison, Anthony Sorrentino decides to break the family "omerta", or the code of silence. Sitting his detective nephew down in a prison conference room, Sorrentino narrates the stories of crime, extortion, and unsolved murders that only he and the walls of his renowned restaurant were the only witness to....