David Attenborough presents survival techniques used by arthropods, who comprise 80% of the animal kingdom, and are vital to ecosystems on all continents except the Atarctic: insects, spiders and scorpions. Rapid and boundless evolution continuously creates new species, adapting to conditions and often in a never-ending arms race between predators and prey. Poison and mimicry are taken to the extreme, but also macabre forms parasitism and other secretions, like hot liquid or deterrent odors.