There are apartments in cities around the world, where the lights do not go on at night. The apartment is empty. And it's hard to tell who owns it or where the money to buy the apartment came from.
And that's because, some of that money is from questionable origins. If you have a lot of money to hide, you can park that cash in real estate. You hide the money in plain sight. You turn a fancy apartment into a giant piggy bank or secret vault.
On today's show, the international quest to try answer a simple question: Who owns Apartment 5B?