The Isabella Stewart Gardner Museum Heist (1990):
The Isabella Stewart Gardner Museum in Boston was targeted in one of the largest art heists in history. On March 18, 1990, two individuals disguised as police officers stole 13 pieces of artwork, including works by Vermeer, Rembrandt, and Degas. The stolen pieces, valued at over $500 million, have never been recovered, and the case remains unsolved.