Everworld is a place that Christopher and the others were drawn to when Fenrir, a giant wolf, tried to kidnap Senna from earth so that Loki could use her for his own cruel purposes. The rules of physics as they apply on earth do not necessarily apply to Everworld. For instance, the force of gravity in Everworld is not constant but varies from place to place. When the teenagers plummet from an opening in the wall of Loki's castle in Searchfor Senna, they slowly plunge into the pool below. What should have been a bone-crushing disaster on earth is instead a splashing but harmless dive. On the other hand, a fall in Ka Anor's land is a nasty business, with sharp, upward pointing stones seeming to be under every precipice.

"That's Everworld," Christopher says.

"A universe within or beside or next door to the real universe. Totally different...