He was once the Russian president's number one fan. Now, he calls himself “Putin's number one enemy.” And he might be onto something. Last month, Bill Browder was arrested outside of his Madrid hotel room by Spanish authorities under an order from Russian Interpol. As the architect behind the Magnitsky Act, a U.S. law that places sanctions on corrupt Russian officials, it was not the first time Browder came under fire by the Russian government. Browder joins Forum to talk about how he went from being the largest foreign investor in Russia to being the country's biggest critic.