Federal agents tried for more than three decades to penetrate the deepest secrets of Chicago's organized crime family - the names of those responsible for 18 ruthless murders aimed at silencing witnesses and meting out mob vengeance. They even called the investigation Operation Family Secrets. Their patience was rewarded six years ago when a mob hit man began to spill the family secrets as part of a deal to keep himself out of the execution chamber. And starting this week, three aging dons of the Chicago underworld convicted in September 2007 as a result of that testimony are due to receive long sentences - quite likely life. Two alleged henchmen also convicted after the 10-week Family Secrets trial are expected to get long sentences as well. "These were the main guys who ran the crime syndicate - they were ruthless, they were absolutely ruthless," says retired police detective Al Egan, also a former longtime member of an FBI-led organized crime task force. Wisecracking mob boss Joseph "Joey the Clown" Lombardo, 80; convicted loan shark and hit man Frank Calabrese Sr., 71, and James Marcello, 66, all face a maximum punishment of life in prison. Former Chicago police officer Anthony Doyle, 64, and convicted jewel thief Paul Schiro, 71, weren't convicted of any murders but the jury found them guilty of participating in what prosecutors say was a long-running conspiracy that included killings, gambling, loan-sharking and squeezing businesses for "street tax." The case is a major success for the FBI in its war on the mob. "It led to the removal or displacement of some of the most capable guys in organized crime," says author John Binder whose book, "The Chicago Outfit," tells the story of organized crime in the nation's third largest city. "And it sends a strong message to members of organized crime: Do you really want to be the guy at the top? Because we're going to get you in the future." Lombardo is the most colorful defendant. He was sent to federal prison in the 1980s for conspiring with International Brotherhood of Teamsters President Roy Lee Williams and union pension fund manager Allen Dorfman to bribe Nevada Sen. Howard Cannon to help defeat a trucking deregulation bill. Cannon was never charged with any wrongdoing and the bill became law with his support. When Lombardo got out, he resumed life as the boss of the mob's Grand Avenue street crew, prosecutors say. He denies it but his attorney, Rick Halprin, told the trial he ran "the oldest and most reliable floating craps game on Grand Avenue." When the Family Secrets indictment was unsealed, Lombardo went underground for nine months. When he was brought before Zagel, the irrepressible clown quickly lived up to his nickname. The judge asked him why he had not seen a doctor lately. "I was supposed to see him nine months ago," Lombardo rasped, "but I was - what do they call it? - I was unavailable." But the jury found him responsible for gunning down a federal witness. The jury also found Calabrese responsible for seven murders. His own brother, Nicholas Calabrese, 66, testified that Frank liked to strangle victims with a rope and slash their throats to make sure they were dead. Nicholas Calabrese became the government's star witness after he dropped a bloody glove near the scene of a mob murder. He agreed to talk out of fear that agents would match his DNA to that on the glove and he would be sentenced to death. Marcello was at one time the mob's big boss, according to federal investigators. The jury held him among those responsible for the murder of Anthony "Tony the Ant" Spilotro, at one time the Chicago mob's man in Las Vegas and the inspiration for the Joe Pesci character in the movie "Casino." Spilotro and his brother Michael were found buried in a shallow grave in an Indiana cornfield. Doyle is the only one of those convicted at the trial who is not accused of direct involvement in the murders.