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."