Twins Rachel and Theo Matheson are saved from death by a kindly and mystical stranger. Eight years later when they visit Auckland they find they have been chosen for a momentous task against the forces of evil.
A sightseeing trip to Auckland's dormant volcanoes brings further evidence that the twins have a dangerous mission. Is Mr Jones' guardianship enough to protect them from the sinister Mr Wilberforce and the slimy creatures which lurk in the lake?
Rachel and Theo are embroiled in a life and death struggle between Mr Jones and the enemy.
Rachel's sleep is disturbed by a telepathic cry for help. Mr Jones' voice seems to drift through the fog from the weird Wilberforce house and the twins steal through the night to his rescue.
Rachel and Theo learn about the aliens' secret labyrinth and are in great danger.
Rachel and Theo learn from Mr Jones about the strategy they must employ if their planet is to be saved. They discover the truth of Mr Jones' warning "Any Shape, Any Form".
The Wilberforce's seem foiled as Mr Jones and the twins strike out for Rangitoto Island armed with their magic weapons.
Time is running out as Rangitoto is ablaze and crimson. Ricky is left as a decoy as the twins and Mr Jones struggle towards their final goal, not realising just how ruthless the aliens are.
