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Treasure hunters are returning to the wreck of a gold-laden ship that sank off the coast of South Carolina nearly 160 years ago, reviving an effort begun in 1987 by a colorful salvage diver who recovered millions from the site before stiffing partners and vanishing.

Odyssey Marine Exploration, a Florida-based deep-ocean exploration company, left port late last week to recover what could be tens of millions of dollars in gold that went down with the SS Central America and now rests a mile-and-a-half under the sea some 160 miles off the Palmetto State's coast. The sunken treasure was first found by Tommy Thompson, and has been the subject of a protracted legal battle — not to mention a best-selling book. Thompson, who sold salvaged gold bars and coins to a California mint for $52 million before going on the lam, remains a wanted man after failing to appear in an Ohio court in 2012. The 62-year-old seasoned sailor and diver is accused of cheating his team of nine technicians of at least $2 million, and they have been fighting for their cut in court for years.

If Odyssey is successful, it and the technicians could see a major payday.

“From what our research team has uncovered, along with the data collected by researchers for the court-appointed receiver, there is potentially a substantial amount of gold left on the site, along with some other interesting artifacts,” Mark Gordon, the company’s chief operating officer and president, told FoxNews.com in a statement. “As importantly, there is a tremendous amount of scientific and archaeological knowledge that we will document from this deep-water site. It is exciting for us to be a part of the next chapter of this great American story and we look forward to sharing the results of our work.”

Estimates of how much gold was on the ship when it went down have ranged as high as 10 tons. Less than 5 percent of the site was investigated by Thompson’s team in the late 1980s and the U.S. District Court for the Eastern Division of Virginia ruled last May to appoint a receiver to supervise resumption of the recovery mission. Gold was valued at about $19 per ounce in 1857; today it sells for around $1,300 an ounce. Bob Evans, of Recovery Limited Partnership, the court-appointed receiver that hired Odyssey, told Bloomberg there may be up to $86 million of gold still lying on the ship.

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“We expect the project to move forward quickly since we have access to all the previous records and images, which provide us with a great overview of the shipwreck,” Gordon said in a statement. “This has allowed us to begin planning operations that will focus on the most interesting and prospective areas of the site after we have completed a pre-disturbance survey and high-resolution photomosaic.”

The wreck lies too deep for humans to dive, but that won't stop the salvage operation. Using its research vessel, the Odyssey Explorer, the company will use an 8-ton remotely operated vehicle (ROV) called Zeus to scan the ocean floor while the operation is directed by an archaeologist and project manager thousands of feet away.

“The SS Central America is one of the greatest shipwreck stories of all time,” Odyssey’s CEO Greg Stemm said in a statement. “We’re very familiar with mid-19th century paddlewheel shipwrecks, as well as the range of artifacts that are likely to be on the site … The SS Central America is less than half the 15,000 feet depth of the SS Gairsoppa, from which we successfully recovered nearly $80 million in silver over the past two years.”

The ship, originally launched in 1852 as the SS George Law, was in continuous service on the Atlantic leg of the Panama route between New York and San Francisco. When it sank on Sept. 12, 1857, killing at least 425 of its 477 passengers, it was carrying a large consignment of gold ingots and freshly minted U.S. $20 Double Eagle coins. The sheer size of the loss was so large that it triggered public confidence in the economy to fall, leading to what’s known to historians as the Panic of 1857. The ship was immortalized in the best-selling book, “Ship of Gold in the Deep Blue Sea.”

Michael Frevola, a maritime attorney in the case, told FoxNews.com in 2012 he had a copy of the 1999 book on his desk during an interview with FoxNews.com. The 507-page national best-seller details Thompson’s trip to the bottom of the Atlantic, but the ensuing legal fight is worth an entirely separate book, he said.

“It’s at a point that a book could be written about this is not unfathomable,” Frevola said in 2012. “It’s a good read.”

Thompson, meanwhile, remains wanted as of Thursday by the U.S. Marshals Service, which began using digital billboards in Ohio and Florida last year to locate the fugitive treasure hunter and his 45-year old assistant, Alison Antekeier, whose arrest was ordered by a judge after they failed to appear in court in August 2012.

Thompson reportedly grew up in central Ohio and spent much of his adult life in Columbus. Antekeier also lived in Columbus until she moved with Thompson to Vero Beach, Fla., where the couple has been living as recently as 2012, U.S. Marshals Service officials told FoxNews.com.