Within the last couple weeks two major art heists were pulled off. In one, three masked men with guns walked into a private Zurich museum, grabbed four 19th-century masterpieces worth a combined 163 million, tossed them into a van and sped off. And then last week, two Picasso paintings worth 4.4 million were stolen from a small gallery also near Zurich. Together the thefts make for one of the most dramatic periods in art heist history. Thomas Hoving is the former director of the Metropolitan Museum of Art. He's written dozens of books about art history, and he knows a lot about where art ends up after it gets stolen.