In a genre so dominated by gruesome murders and, to a far lesser extent, missing-persons cases that seldom end well, Netflix's This Is a Robbery: The World's Biggest Art Heist offers a welcome reprieve. Think of it as a rare gem -- or, more appropriately, a Rembrandt -- among true-crime documentaries.

That's not to say this mystery ends happily, mind you. Nearly 31 years after after two men posing as police officers walked into the Isabella Stewart Gardner Museum in Boston and walked out 81 minutes later with 13 works of art, by Rembrandt, Vermeer, Manet and others, the crime remains unsolved. In that time, the reward money has ballooned from $1 million to $10 million, while the list of persons of interest has dwindled to just one; in the words of one defense attorney, “Everybody who did the robbery is whacked or died of natural causes or, some might say, unnatural causes."

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This Is a Robbery

However, that lack of a solution, and closure, doesn't detract from director Colin Barnicle's four-episode docuseries, now streaming on Netflix. Instead, that may very well make it easier for viewers to become absorbed in the twists and turns, the theories and the list of colorful (and unsavory) suspects. The question becomes not so much who did it, but rather why they chose the works they did -- some are priceless while others have relatively little value -- and, most importantly, what they did with them. After all, as difficult as it is to steal Vermeer's The Concert and Rembrandt's The Storm of the Sea of Galilee, it's far harder to sell them.

Blending archival news reports and security footage with modern-day interviews with former museum employees and law-enforcement officials, journalists, attorneys and eyewitnesses, This Is a Robbery reaches back long before the early hours of March 18, 1990, to the Gardner's 1903 opening, to establish a building in need of improvements, including an upgraded security system and better-paid guards. One of those guards, Rick Abath, immediately drew the interest of the FBI: He buzzed the two uniformed men into the museum, and then walked out from behind the desk hiding the button that could alert the actual police; what's more, the robbers appeared to possess inside knowledge of the Gardner and its collection.

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This Is a Robbery

However, suspicion just as swiftly turned to notorious New England art thief Myles Connor, who's interviewed for the docuseries (he had a pretty good alibi, as he was in prison at the time for an earlier art heist). Or maybe it was the Irish mob, and the nearly $500 million worth of artwork was shipped overseas, with the money going into the coffers of the Irish Republican Army.

Investigators, and Barnicle, settle upon members of the Boston Mafia: Bobby Donati, a one-time associate of Myles Connor, and Bobby Guarente are thought to have planned the heist, while a crew from Dorchester, Massachusetts, led by Carmello Merlino pulled it off. But, despite plenty of suspects, and a plausible route for the works out of Boston, the FBI uncovered no real evidence -- not even after raiding the home of a Hartford, Connecticut, gangster believed to have received the stolen goods.

This Is a Robbery is perhaps its most fascinating when it explores the potential motive for the heist. Although it's possible the crooks were hired by a wealthy collector to break into the Isabella Stewart Gardner Museum, the randomness of the stolen works argues against that. The more intriguing theory (and the one that pulls back the curtain on the world of art crimes) is that the Gardner pieces were intended to be used as leverage to negotiate for lighter prison sentences in other crimes. It's a strategy previously utilized -- some may even say perfected -- by none other than Connor himself.

But if that were the plan, none of those thought to be involved ever turned in their get-out-of-jail-free cards, for the benefit of themselves or their friends. All of those men are dead now except David Turner, a Merlino gang member released from prison in 2019 after serving 21 years for his role in a planned 1999 armored-truck robbery. Although Turner's sentence was significantly (and secretly) reduced from 38 years, it's unclear what he offered the government in return. It certainly wasn't the location of the stolen artwork, however, because, three decades later, empty frames hang in the galleries of the Isabella Stewart Gardner Museum, and the $10 million reward remains unclaimed. And Turner, by all accounts, still isn't talking.

Directed by Colin Barnicle, the four-episode docuseries This Is a Robbery: The World's Biggest Art Heist is streaming now on Netflix.

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