WPC Gwen Cooper is at the scene of a brutal murder, when the "special ops," known only as Torchwood, arrive. After witnessing the group bring the dead man back to life, Gwen goes in pursuit of this mysterious organisation, only to see weirder things than she could ever imagine existed. Soon after, she begins to regret giving in to her curiosity, when she meets Captain Jack Harkness.

At 8.45am, every child in the world suddenly stops, chanting the words "we are coming" again and again. Whilst investigating, the remaining Torchwood team face greater personal and professional challenges than ever before, having to work with their numbers depleted.

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.

Convicted child killer Oswald Danes is executed for his crimes and when he miraculously survives his fate a series of events is set in place that forces CIA Agent Rex Matheson to investigate a global event. His investigation leads him from America to Wales and an old defunct British Institute - Torchwood.

As the Torchwood team launch a final, desperate mission against the seemingly undefeatable Three Families, they realize it may come down to the ultimate sacrifice.