Forgers and fraudsters trusted him for decades — but he was an undercover FBI art detective.

There are people who devote their entire existence to a very specific mission, whether it is to protect their fellow man in wartime contexts, or to safeguard the precious cultural assets that make up a nation's current and historical identity. Like FBI investigator Ronnie Walker, who prepared for years to go undercover to infiltrate the U.S. art theft scene.

Jerry Christy, a notorious thief in the industry, was the object of Walker's attentions, who was interested in his capture and subsequent achievement in the fight against these kinds of scams. So in 2007, the FBI agent posed as a would-be buyer, authenticator and dealer in stolen artwork, specifically during an investigation against Christy, who was identified as the person responsible for the theft of a Rembrandt.

Today's reference article recounts the events introduced here, explaining how the undercover mission took place and briefly presenting the history of the Bureau's art crime team.