CHICAGO (WLS) -- A now-elderly hoodlum who led the Chicago mob's London diamond heist in 1980 is back on the street and his Outfit accomplice has one foot out the door of the U.S. Bureau of Prisons, staying in a Chicago halfway house.Together, career mobsters Art Rachel and Jerry Scalise stole the famous Marlborough diamond from a U.K. jewelry store on September 11, 1980.Now mob-watchers are wondering whether the Outfit duo is planning a 45-carat reunion when Rachel joins Scalise in newfound freedom from the Bureau of Prisons.It was one of the most daring heists in Outfit history. Two men dressed as Arab sheikhs held up one of London's high end jewelry stores and walked out with hands full of gemstones, including the near million-dollar Marlborough.Unfortunately for Art "the Genius" Rachel, he didn't live up to his mob nickname. The Genius was arrested at O'Hare Airport on his return trip with fellow Outfit thief Jerry "Monk" Scalise.But authorities never recovered the stolen diamond and some investigators have long suspected that Scalise and Rachel somehow managed to hide the 45-carat stone.Rachel has always denied knowing what happened to it, including during a 2001 interview with the ABC7 I-Team when he said he'd already spent the money.When pressed by investigative reporter Chuck Goudie on how much he made from the diamond deal, Rachel said it was "none of your business."After doing time for the jewel heist, Rachel and Scalise returned to Chicago and to the criminal world.In 2012, the pair and a third aging gangster were arrested during a suburban crime spree in which they targeted an armored car and the home of a late Chicago mob boss. Authorities found the men with burglary tools and a weapons cache. They were sent to prison -- again.Now, the I-Team has learned that Jerry Scalise is out from behind bars, having completed yet another prison term. He was released in late June.His Marlborough diamond partner Art Rachel is also out of the penitentiary and residing in a Chicago halfway house.Both men are 81 years old and authorities know that they know what happened to the Marlborough diamond.Mobologists have had many theories about the fate of the Marlborough diamond: that the thieves mailed it to themselves or someone else, buried it in the U.K. on the way to the airport, or handed it off to an accomplice - who then cut it into a hundred small diamonds.