Every year, more than half a million people worldwide either die or lose limbs from poisonous snakebites. See how a global crisis has emerged due to inadequate supplies of antivenom. Examine the biology of venomous snakes, the pharmacology and biochemistry of antivenom, its use in treating disease, and the politics of bringing life-saving antivenom drugs to market. Meet the doctors, herpetologists, medical researchers, conservationists, and patients working together to address an international crisis.