Six men are currently appearing in a southern French court, charged with stealing four paintings valued at €22 million ($29.3 million) from Nice's Musée des Beaux-Arts in 2007. And in a turn of events that has taken on all the trappings of a crime drama, they are accusing a well-known F.B.I. art-crimes expert of inciting them to commit the robbery.

At lunchtime on August 5, 2007, a group of masked men dressed in blue janitorial uniforms entered the museum, ordered the staff and visitors to lie on the floor, and proceeded to take four paintings down from the walls: "Allegory of Water" and "Allegory of Earth" by Jan Brueghel the Elder, "Cliffs Near Dieppe" by Claude Monet, and "Lane of Poplars at Moret" by Alfred Sisley. The Monet and Sisley works were on loan from Paris's Musée d'Orsay, according to AFP. Museum employees say that the men were armed, which they dispute. The leader of the gang was a former small-time thief named Pierre Noël-Dumarais who is now 64 years old. "It was a job by bumbling crooks, which they pulled off because the museum was not at all protected," Noël-Dumarais's attorney, Ludovic Depatureaux, told TF1. The thieves were in and out of the museum in just five minutes.

But the plot thickens due to the involvement of another man, Bernard Ternus, who is originally from France but moved to Miami in 2007. He allegedly helped plan the heist in order to sell the paintings to a wealthy American, Bob Clay. Ternus had met with Clay on a Colombian drug kingpin's yacht, where he saw the unscrupulous American purchase priceless paintings with gold and diamonds while partying with bikini-clad call girls, according to L'Express. In reality, however, "Bob Clay" was Robert K. Wittman, an F.B.I. agent who founded the agency's art crime division, and the scene on the boat was all staged. From his jail cell, Pierre Noël-Dumarais wrote to Nice-Matin that "the Nice theft wouldn't have happened if Wittman hadn't put on the pressure." When Ternus arranged for the sale of the stolen paintings in June 2008, the French art-crime squad swooped in, recovered the Brueghel, Monet, and Sisley paintings, and arrested the thieves. Ternus was tried in the U.S. and is currently serving a sentence of five years and two months in Miami.

In his 2010 memoir, "Priceless: How I Went Undercover to Rescue the World's Stolen Treasures," Wittman — who now runs an art security consulting business in Philadelphia — recounted his efforts to solve a 1990 theft of artworks including a Vermeer and a Rembrandt seascape from Boston's Isabella Stewart Gardner Museum. On a tip that the paintings could be in the hands of the Corsican mafia, he sought out Ternus, who claimed to have mob connections, and posed as a shady art collector. Noël-Dumarais's attorney accuses Wittman — whom the French media are calling the "American super-cop" — of "having French heritage pillaged." "It's police provocation, which is illegal in France," the attorney told L'Express. Wittman, however, told the Daily Telegraph that he did not incite the men to commit the crime but set up the sting when they offered to sell him the stolen works. "I don't think anything I did 'encouraged' anyone to obtain Chechen hand grenades and semi-automatic pistols in order to commit armed robbery," Wittman said. "It is a fanciful defense at best — at worst it is a defense of desperation used only when criminals are caught."