Isabella Stewart Gardner Museum art theft (unsolved)

On March 18, 1990, two men posing as police officers entered the Isabella Stewart Gardner Museum and stole 13 works of art, including pieces attributed to Vermeer and Rembrandt, in what remains the largest unsolved art theft in U.S. history. The stolen works are estimated collectively to be worth around $500 million and have not been recovered. The FBI maintains an open investigation and the museum continues to offer a reward for information leading to recovery.