Five months ago, the apocalyptic Jolt turned the majority of mankind into the atavistic savages Jay Garvey calls Hyenas, on account of their insane, shrieking laughter.
 
A terrified Jay is tempted from his bolt-hole in a Liverpool bookshop when he learns the whereabouts of the only boat that hasn't been scuttled by the deranged militia leader known as Sergeant Pepper.
 
As a brutal winter closes in, Jay and the small band of survivors he encounters along the way, the Book Club, must avoid death and capture to take advantage of this single, slim window of escape.