'The Millennium, Mel: the last New Year's eve of the Twentieth century. But it's definitely not party time.'

England, 1999: the Doctor and Mel have come to London to celebrate the new year with old friends - and to heal old wounds. But others are making more sinister preparations to usher in the new millennium. A software house is about to run a program that will change the fabric of reality. And an entity older than the universe is soon to be reborn.

When Anne Travers' fear of the great Intelligence and millionaire philanthropist Ashley Chapel's secret researches combine, London is transformed into a dark and twisted mirror image populated by demons and sorcerers. Only the Doctor can put things right, but his friends have also been shockingly changed and he cannot trust anybody - least of all himself.