The Demi-Monde is the most advanced computer simulation ever devised. Created to prepare soldiers for the nightmarish reality of urban warfare, it is a virtual world locked in eternal civil war. Its thirty million digital inhabitants are ruled by duplicates of some of history's cruellest tyrants: Reinhard Heydrich, the architect of the Holocaust; Beria, Stalin's arch executioner; Torquemada, the pitiless Inquisitor General; Robespierre, the face of the Reign of Terror. But something has gone badly wrong inside the Demi-Monde, and the US President's daughter has become trapped in this terrible world. It falls to eighteen-year-old Ella Thomas to rescue her, yet once Ella has entered the Demi-Monde she finds that everything is not as it seems, that its cyber-walls are struggling to contain the evil within and that the Real World is in more danger than anyone realises.

The shadows of war grow ever darker across the Demi-Monde. Norma Williams knows she was a fool to be lured into the virtual nightmare that is the Demi-Monde. When the agent sent in the game to save her goes rogue and a long forgotten evil is awoken, it falls to Norma to lead the resistance. Lost, without a plan, and with the army of the ForthRight marching ever closer, she must come to terms with terrible new responsibilities and with the knowledge that those she thought were her friends are now her enemies. To triumph in this surreal cyber-world she must be more than she ever believed she could be . . . or perish.

The Demi-Monde was intended to train today's soldiers to fight tomorrow's wars - but its creator had its own secret agenda, and now no one can be allowed to stand in its way . . . Eight thousand years ago the Deluge destroyed the empire of the Lilithi, setting the race of super-warriors known as the Grigori loose in the outside world. They have lain hidden until now when - thanks to the creation of the dystopian virtual reality that is the Demi-Monde - they at last stand ready to achieve mastery of the Real World - and to cull HumanKind in the Final Solution. Three girls stand between them and Norma Williams, trapped in the nightmare that is the Coven, the viciously misandric Sector of the Demi-Monde; Ella Thomas, enslaved by the spirit of Lilith-come-again; and Trixie Dashwood, consumed by her hatred for Heydrich and his evil ForthRight.

For thousands of years the Grigori have lain hidden, dreaming of the day when they will emerge from the darkness. Now that day draws close. Norma, Trixie and Ella fight doggedly to frustrate these plans, but they need help. Percy Shelley must lead Norma to the Portal in NoirVille so she can return to the Real World. Trixie's father must convince her that, if she is to destroy the Great Pyramid standing in Terror Incognita, she must be prepared to die. And Vanka Maykov - though not the man she knew and loved - must guide Ella to the secret enclave of the Grigori, where she will face the most chilling of enemies. In this explosive finale to the Demi-Monde series, our heroes will come to understand that resisting evil will require courage, resolve... and sacrifice.