This is a story about hot stuff.

Stolen property.

Things that fall off the back of a truck.

Mob guys have always traded in this kind of contraband, selling goods for about 10 cents on a dollar. This is possible because there’s no upfront cost. All the proceeds are profit. During the 1990s, the Joey Merlino crew made several scores built around tractor trailers stolen from storage facilities and shipping yards along Delaware Avenue.

There were ceiling fans and sweat suits and bicycles.

There was also a trailer load of baby formula. But the wiseguys couldn’t find a market and ended up abandoning the trailer at a rest stop along the Jersey Turnpike. The fear in law enforcement circles and in the art world is that something like that may have happened to the paintings stolen from the Gardner Museum up in Boston back in 1990.

The FBI claims that some of the art work—total value $500 million—made its way to Philadelphia.

“We’ve determined in the years after the theft that the art was transported to the Connecticut and Philadelphia regions,” said one of the Boston FBI agents spearheading the investigation. “But we haven’t determined where the art is right now.”

That was five years ago. It was part of a press release announcing “significant investigative progress.” At the time there was a $5 million reward for information leading to the return of the paintings.

By the end of last year, the reward was up to $10 million.

So much for significant progress.

It’s been called the largest art heist in American history and the fact that the FBI has come up empty after 27 years is embarrassing, but not totally unexpected. Dealing in stolen art work is a sophisticated business that often takes place on an international level in a very cosmopolitan and elite criminal underworld.

It’s hard to imagine members of the Merlino crew—or almost any other mob crew for that matter—traveling in those circles. It’s even harder to imagine that any wiseguy who had a shot at collecting a $10 million reward wouldn’t go for the bucks.

The statute of limitations has expired on the theft. The reward is a no- questions- asked kind of deal. If those paintings came through Philadelphia and the local mob family was involved, then somebody is leaving $10 million on the table.

Given the financial track record of this group, that doesn’t seem likely.

Yet the rumors and stories persist.

On March 18, 1990, two men posing as Boston police officers showed up at the door of the Gardner Museum shortly after 1 a.m. in the morning. Think about the timing. Much of Boston was still in Saint Paddy’s Day mode, partying in the extreme. The guard at the museum ignored protocol and let the “cops” in. He and another guard were tied up, and in less than two hours, 13 pieces of art, including paintings by Vermeer, Manet, Rembrandt and Degas were cut from their frames, rolled up and whisked away.

The Philadelphia connection surfaced much later and was built around a group of Boston wiseguys and wannabes affiliated with Bobby Luisi who in the mid 1990s forged an alliance with Merlino and company in what Luisi said was an initial step toward forming his own crime family.

“We were in a war up there,” Luisi explained in a recent telephone conversation from his home outside of Nashville where, reborn as the Reverend Alonso Esposito, the former mobster is now a born-again preacher with his own television ministry (but that’s a story for another day). “I only hooked up with Joey to get made and to make my own crew.”

Luisi said he and George Borgesi, a top Merlino lieutenant, traveled to Boston in 1997 and formally initiated a half dozen of Luisi’s associates into the Philadelphia mob. One of those initiates was Robert “The Cook” Gentile.

Luisi’s plans to start his own family were short circuited by the FBI. He was caught up in a sting operation and indicted for drug dealing. Merlino and company faced racketeering charges in Philadelphia. The organization literally came undone.

But Gentile remained on the streets and at various times has talked about some of the art work. He and another Luisi associate, Robert Guarente, have been identified as possible suspects in the heist. Guarente died in 2004, but his wife has said the he told her he had given two of the paintings to Gentile. Gentile, now in his 80s and serving time for drug and weapons offenses, has denied this, although in one interview he allowed as how he might have alluded to knowledge about the stolen art work, but only as part of a scam.

Luisi doesn’t know specifics, but he’s somewhat skeptical.

He said Guarente once told him he knew where some of the paintings were buried in Florida and asked Luisi if he knew anyone “who could move them?”

“I told him, ‘I’m not a fence,’” Luisi recalled. “That’s a different world. He never mentioned it again.”

Luisi said that while Guarente knew, and sometimes did business with, a group of high end burglars and jewelry thieves, he wasn’t capable of dealing in valuable pieces of stolen art. Neither, he said, was Gentile.

“Don’t get me wrong,” Luisi said. “These were street guys. They could do a lot of things. But art work? I don’t think so.”

The idea that any of the paintings made their way to Philadelphia doesn’t seem to make sense.

Bob Wittman, a retired FBI agent out of the Philadelphia office who specialized in tracking stolen art (he co-authored the book “Priceless” with former Inquirer reporter John Shiffman) said he was on the job at the time of the heist and during the period when the paintings may have come through Philadelphia.

Given the stream of information coming the feds way from informants and electronic surveillance, Wittman figures he or one of his FBI colleagues would have heard something. And given the reward that’s just sitting there, he also believes someone would have stepped forward by now to try to collect.

“I can’t say it didn’t happen, but it doesn’t make sense,” Wittman said in an interview a few years ago. “What would be the purpose of bringing the paintings to Philadelphia? You want to show them to somebody, they just hop on a plane and fly to Boston.”

And the reward that sits there?

“It’s free money for them,” he added. “You know those guys. What do you think?”

The Philadelphia mob dealing in priceless and valuable commodities is a troubling thought. Back in the mid-1990s, a wiseguy in Cleveland had stolen a Lamborghini valued at about $120,000. It was a 1988 fuel-injected 500S model anniversary edition.

But the car was so unique that he couldn’t find a buyer in the Cleveland area. Through a series of deals, the car ended up in Philadelphia and in the hands of one of Merlino’s top guys, Marty Angelina. The Lamborghini was stashed in a small garage in South Philadelphia.

Word got out that the FBI was poking around and, according to court testimony, Angelina decided to move the car. But the battery was dead. He rented a panel truck, but the truck didn’t have a ramp. So two wooden planks were set in place and Angelina and an associate tried to push the $120,000 vehicle into the truck.

The Lamborghini slipped off the planks. The front end and bumper were damaged.

The wiseguys eventually sold the car—unknowingly to an undercover FBI agent—for $5,300.

Not even ten cents on the dollar.