In the past month and a half, a $200,000 Picasso sketch titled “Tete de Femme” was stolen from a San Francisco gallery, a $350,000 Fernand Léger was lifted from a New York gallery, and eleven paintings valued at $387,000 were stolen from a gallery in Toronto. High profile arts heists are on the rise around the world and, according to the FBI, the international black market for art and cultural property is now worth $6 billion annually. How does one go about stealing a great work of art, and how did art become such a commodity? We’re speaking with Joe Medeiros, director of the documentary “The Missing Piece,” which tells the story of how the Mona Lisa was stolen from the Louvre, 100 years ago this week.