On April 30, 1979, Carl Gaimari, a wealthy commodities trader from Chicago, was shot and killed in his home while his wife and young children were locked in a closet.
Two weeks later, Arthur Jones, Gaimari's friend and fellow trader on the Chicago Board of Trade, told his wife he had a business meeting, walked out of his suburban Chicago home, drove off in his silver Buick and vanished without a trace.
Mike Stuto, a special agent with the Office of Inspector General, Social Security Administration, worked the case. "They suspected Arthur Jones fell victim to foul play and organized crime due to his gambling debts," he says.
But halfway across the country, a man named Cliff Goodenough was slowly piecing together the clues that would unlock the mystery of Jones' disappearance.
Goodenough, a nurse at a VA hospital, says his life had been in shambles because of a decades-long battle with the IRS. He says bogus income kept showing up on his Social Security for earnings at a casino in Las Vegas.
Tens of thousands of dollars popped up year after year, but Goodenough says he never traveled to Vegas, let alone won any money there. "I have work records to show I couldn't have been there working or gambling. Doing either one," he says.
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But each year he faced the same thing; income was added and then he was forced to spend months clearing his name. "Basically your financial life is held hostage. It's ridiculous. You feel like you are banging your head against a wall," Goodenough tells CNBC.
But then in 2004, two bombshell letters from the IRS changed everything for Goodenough. The first proved that someone else was using his tax ID number. "A letter that says, by the way, you have to turn your property over to the individual who has your social as well," he says.
The second was even more powerful. It was the key to unlock not only his own IRS nightmare but would also help solve the decades-old mystery about Arthur Jones. The second letter was sent to Goodenough's Glendale, Ariz., home with his tax ID number, but attached to the name "Joseph Sandelli."
He did a search, found Sandelli's phone number in Las Vegas and called him. "He seemed to be friendly, very cordial. And after a few conversations with him, I realized later on that the information that I was able to obtain I was the one feeding it to him," he says. "I was like, I was born in Lake Forest, Illinois, and he then would say, oh so was I."
Sandelli claimed that there was a mix up at the post office in their home town and made Goodenough an offer. "He offered to get a new Social Security number to get it straightened out," he says. "And when you think about that, why would a guy 65-70 years old who worked his whole life and now he has his Social Security he's going to draw on, why would he offer to change his Social Security number?"
Goodenough didn't buy Sandelli's story and called Senator John McCain's office for help. And that's when Agent Stuto got involved.
Stuto and another agent confronted Sandelli at his house in Las Vegas, a few miles from the Rampart Casino where he worked as a bookie.
"The million dollar question: What is his true identity? And what's he hiding from?" Stuto tells CNBC. Sandelli told the agents that he was never married and didn't have any children but in a shocking admission, told them that his name used to be Arthur Jones.
"We came across an Arthur Jones in Chicago, however, in our records this Arthur Jones was deceased," Stuto tells CNBC. Stuto reached out to Jones' widow who was still living in Chicago. "The first words out of her mouth were, "On May 11, 1979, my husband left. He was a missing person."
It became clear that this was Arthur Jones and that Stuto had found her deceased husband. "That was the moment where you almost drop the phone," he tells CNBC.
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Stuto went back to the house for another round of questions with the man who had gone by the name Sandelli for decades. During this final meeting, he admitted that his personal and financial problems became so big that his only option was to just walk away.
He told the agents that he had major gambling debts, but it was something at the Board of Trade that put him over the edge. "During one trade, instead of selling 100,000 bushels of corn, he mistakenly bought 100,000 bushels of corn," Stuto says.
After that, his life in shambles, Jones decided to walk away from his wife and kids and start a new life. He paid a friend $800 for a new tax ID number which happened to belong to Cliff Goodenough, and then disappeared. Stuto says there was absolutely no emotion in Jones' voice—no remorse for leaving his family and no curiosity about the lives they lived without him. He told Stuto, "When I left, I left."
Jones eventually pleaded guilty to one count of fraud and was sentenced to three years probation. He was also ordered to pay back the benefits his family received and nearly $11,000 to Cliff Goodenough.
The two finally met face to face at Jones' sentencing. "We never locked eyes, I looked at him most definitely, but he looked at the ground, he looked away, he knew I was looking at him," Goodenough says. What Goodenough really wanted from Jones? An apology.
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"I want a hand-written letter apologizing not so much to me, but to my wife for the amount of anguish and the amount of times she was upset year after year dealing with the IRS and the calls and the call backs," he says, "but what her husband was like after that, which was not a very pleasant person to be around to say the least."
And in another twist to this incredibly bizarre case, Carl Gaimari's widow was recently charged in the 1979 death of her husband. She originally claimed that she was locked in a closet on the day her husband was killed, but prosecutors told a judge that investigators recorded a recent telephone conversation during which they claim that Jacquelyn Greco said she "had a plan to kill the victim."
Only a week after her husband's death, her lover, a Chicago police detective moved into the house. Three months later, in August, 1979, they were married.
—By CNBC's Jeff Pohlman and Michael Tomaso