20/20: Last Days on Earth | 2005
A look at the seven different ways scientists believe the world could end, starting from the least likely to the most likely: 7. Death of a star: gamma ray burst or black hole; 6. Computers become more intelligent than humans and turn against us; 5. Supervolcano; 4. Asteroid; 3. Nuclear War; 2. Plague; 1. Climate Change.