What happens when something is sucked into a black hole? Three decades ago, a young English physicist named Stephen Hawking claimed that when something is sucked into a black hole, it disappears. Most scientists didn't recognize the importance of that claim, but Leonard Susskind and Dutch physicist Gerard't Hooft realized that if Hawking was right, then everything we know about the fundamental laws of the universe would have to be tossed out. Leonard Susskind joins Larry Mantle to talk about his battle with Stephan Hawking over the true nature of black holes, with nothing less than our understanding of the entire universe at stake.