The eyes of the world turn to Britain, as the 456 announce, 'We are here'. As a pillar of fire descends upon London, the members of Torchwood must battle to protect their own families, as the fight gets personal. But will Clem's memories destroy everything?

Torchwood is defenceless and Gwen Cooper stands alone as the final sanction begins. As violence erupts and the world descends into anarchy, an ordinary council estate becomes a battleground where the future of the human race will be decided.