Looming over New Zealand’s largest city, the Rangitoto Volcano has stood dormant for hundreds and hundreds of years. Now, in the depths of its belly, a dark force has gained power, and is waiting for the moment its muscle is unleashed and the world as we know it will disappear forever.

Two twins have been born with a telepathic gift. Theo and Rachel are ordinary teenagers whose lives are blown apart by the sudden death of their mother. After they are sent to live in Auckland, they explore a creepy old house on the edge of a volcanic lake, and discover shape-shifting creatures lurking beneath the city’s volcanoes. Guided by the mysterious Mr. Jones, the twins must rekindle their unique powers if they are to destroy this ancient evil – and save the human race from extinction.

The movie is based on the book by one of New Zealand's most distinguished novelists Maurice Gee. He was among ten of New Zealand's greatest living artists named as Arts Foundation of New Zealand Icon Artists at a ceremony in 2003. And this fantasy classic has made him the winner of 2004 the Gaelyn Gordon Award for a Much-loved Book. Also, the book was adapted into a TV series in the early 1980s.