"This undated file photograph provided by the Isabella Stewart Gardner Museum shows the painting ""Chez Tortoni,"" by Edouard Manet, one of more than a dozen works of art stolen in the early hours of March 18, 1990. On Thursday, Aug. 6, 2015, the U.S. Attorney's Office released a surveillance video showing an automobile outside the rear entrance and an unauthorized visitor entering the museum 24 hours before the robbery. Photo: Courtesy Of Isabella Stewart Gardner Museum Via AP, File / Isabella Stewart Gardner Museum"