In the beginning 11 years ago, two immortal beings decide that it might not be the right time to start an apocalypse.

Having followed the wrong boy for years, Aziraphale and Crowley must try to find the location of the real Antichrist, perhaps the story of Agnes Nutter and her famous prophecies will hold the answer.

Following Aziraphale and Crowley's friendship across the ages; in the present day, Agnes Nutter's descendant Anathema arrives in Tadfield on her own mission to save the world.

Aziraphale and Crowley's friendship is tested to the limit as their superiors catch up with them; Armageddon starts in earnest, as the Antichrist's powers wreak havoc across the globe.

Aziraphale and Crowley race toward Tadfield airbase as they attempt to prevent Adam and the Four Horsemen from starting the apocalypse; one has been discorporated and the other is trapped in a flaming motorway.

Adam, Crowley and Aziraphale must work together to fight the powers of heaven and hell and prevent the apocalypse; they find out the fate that awaits them if they do.