The events depicted in Web are written from the viewpoint of Arnold Delgrange, a man whose wife and daughter were recently killed in a motor collision. They revolve around a failed attempt to establish a utopian colony on the fictional island Tanakuatua in the Pacific Ocean, remote from civilisation. Tanakuatua is now uninhabited by humans, as its native inhabitants were evacuated from the island due to British nuclear testing and were relocated. However a small group of natives defy the evacuation order and placed a curse on any people who returned to the island. When Delgrange and his fellow pioneers reach the island they soon discover it has been overrun by spiders that hunt in packs.