Without triggering a single alarm, a hooded thief smashed open a window of the Musee d'Art Moderne in Paris last week and went on an extraordinary looting spree. Before disappearing into the night, the intruder stole five exquisite paintings, including works by Matisse and Modigliani as well as Picasso's cubist masterpiece "Dove with Green Peas." Experts valued the looted canvases at as much as $124 million.

It's been described as the art heist of the century. But no criminal mastermind was required here. It turns out that the museum had been about as secure as a woodshed. The alarm system had been malfunctioning for almost two months, and while the museum had ordered replacement parts, they had not yet arrived. It also appears that the museum's guards may have been napping-or at least were remarkably inattentive. While cameras filmed the thief pilfering the works, it wasn't until the next morning that someone actually discovered the theft.