There is a hint of Armageddon in the air. According to the Nice and Accurate Prophecies of Agnes Nutter, Witch (recorded, thankfully, in 1655, before she blew up her entire village and all its inhabitants, who had gathered to watch her burn), the world will end on a Saturday. Next Saturday, in fact.
The first message sent to Tom Thorne's phone was just a picture - the blurred image of a man's face, but Thorne had seen enough dead bodies to know that the man was no longer alive. But who was he? Who sent the photograph? And why? While the technical experts attempt to trace the sender, Thorne searches the bulletins for a reported death that matches the photograph. Then another picture arrives.