March 18, 1990

The two cops buzzed the security door at the Isabella Stewart Gardener Museum in Boston. The guard who let them in quickly discovered they weren’t cops at all, but two art thieves in disguise.

What followed remains the single largest property theft in the world. The thieves managed to cart away paintings worth an estimated $500 million, including paintings by Rembrandt, Vermeer, Degas and Manet.

The spaces where the paintings hung have not been assigned new art. Instead, the empty frames stand as a reminder that the art has yet to be recovered, a painful mystery for museum fans.

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