Mona Lisa

Recovered in 1913. Vincenzo Peruggia, a Louvre worker who had helped build the painting's glass case, took it on August 21, 1911; the painter Louis Béroud first reported it missing the next day. Peruggia kept it hidden in his Paris lodgings for about two years, then took it to Florence and was caught trying to sell it to Giovanni Poggi, director of the Uffizi. It was back in the Louvre on January 4, 1914, and Peruggia was jailed for one year and 15 days. The theft matters beyond its happy ending: worldwide coverage of the loss and return is what made the portrait a household image.