Insatiable, marauding aliens, The Nekross, invade the Earth in search of magic. Teenage schoolboy wizard Tom Clarke and his friend Benny Sherwood lead the defense against them.
With the Nekross gone, Tom and Benny's lives return to normal. However, when everyone at Kings Park School begins to behave as if they have become possessed, Tom and Benny fear that their enemies have returned.
The Nekross are back and have brought a new threat in the form of Varg's manipulative new wife, The Lady Lyzera. With the alien Consolidation drilling beneath the school to extract the Earth's core, Tom must strike a deal with Varg.
While Ursula and Michael investigate reports of a red demon on the moors, Benny receives an invitation from eccentric scientist Adam Wright to visit Brook Mill Radio Telescope. Adam is close to reversing the effects of climate change.
Jathro's master plan to rule Earth by harnessing light energy quickly unravels, and the energy begins to leak out into the Earth's atmosphere. Worse still, the energy begins to impact the atomic structure of the entire human race.
With Benny in America, Katie contacts Tom to express her belief that the Blackberry Theatre is haunted. Tom believes otherwise and is proven correct. A tear in the Line of Twilight has brought the witch Old Bethesta back to the Dayside.
Tom and Ursula are stunned when Tom's grandfather, Simeon Swann, returns from the Neverside after 30 years. The family reunion is cut short when Old Bethesta kidnaps Ursula to drain her Magic to help free her own daughters from a spell.
Tom finds himself torn between the exciting world of his grandfather and the grounded, yet unenchanted influence of Michael. When Simeon discovers further evidence of the growing tears in the Line of Twilight, he proposes a great quest.
Tom, Michael, and Simeon are trapped with Varg and Lyzera in a deadly quest for the Key of Bones by the Quest-Master. Negotiating a maze of puzzles in an abandoned castle, the group must work together, knowing any mistake could be deadly.
When Moon learns that Lady Lyzera intends to use the Key of Bones to bargain with, and release, Warlock from his centuries-long imprisonment on the Neverside, he races to Blackhawk Abbey to stop her, leaving the Chamber of Crowe in danger.
Using the Chamber of Crowe as his gateway, Warlock threatens to destroy the Line of Twilight and take his revenge on the Dayside, once and for all. Trapped aboard the Zarantulus, Tom must overcome his deepest fears to save world.