Ten Unsolved Art Mysteries and Heists, from Mona Lisa's Identity to the Isabella Stewart Gardner Museum Theft

A survey published by Art & Object assembles ten enduring art-world conundrums, ranging from the identity of the sitter in Leonardo da Vinci's Mona Lisa to unsolved thefts. The Mona Lisa, painted between 1503 and 1506 and held at the Louvre in France, has drawn speculation for 500 years; many historians argue the subject was Lisa Gherardini, an Italian noblewoman whose husband commissioned the portrait. Crime features prominently in the list, which covers the secret identity of a graffiti artist, suspicious deaths, and unsolved art heists. Among the documented losses is Rembrandt's The Storm on the Sea of Galilee, stolen from the Isabella Stewart Gardner Museum; a photograph taken in March 2018 shows the empty frame where the canvas once hung. The image is credited to the Federal Bureau of Investigation and Wikimedia Commons. The roundup also notes mysteries tied to the scale of prehistoric structures and to the unknown models behind enigmatic portraits, framing the art world as a field with a long history of unresolved questions. The piece was published on October 6, 2026.