A mysterious virus kills most of the world. In England Abby Grant finds herself immune but her husband dead. She determines to set out and find her son Peter, last known holidaying in the Peak District,and on the motorway meets the practical Greg Preston. Tom Price, a convict serving life for murder, kills the only other prison survivor, a warder,and escapes, meeting Anya, a hospital doctor who has seen friends and patients alike die. Al, a wealthy young man, also survives, 'adopting' Najid, an eleven year old orphan. The group ultimately come together whilst Samantha Willis, the only government minister to survive, forms a small caucus in a germ-free complex, killing anyone who may be infected to tries to get in but having to admit the thuggish Dexter as her right hand man.