This episode gives an introduction to the world of venomous animals and how they use their poisons. Venomous creatures such as snakes and spiders are the stuff of human nightmares. Yet toxins are a regular part of the animal world, an essential tool for hunting and defense. From the mighty King Cobra, which can reach over five meters in length, down to the diminutive but lethal Black Widow Spider, we will learn more about them.