In the small, rural community of Shettle children are being viciously murdered. Four men -- schoolteacher Nick Miller, doctor John Kersh, private investigator Chris Blaine and local newspaper editor Alan Michaels -- track the killer, Karl Mitterhaus, down in his house up on the hill and impale him with a spar of wood. His last words as he lies dying send a chill through them all.

Ten years later Shettle has fallen into a decline. It is rife with crime and its inhabitants plagued by ill-fortune. As the tenth anniversary of Mitterhaus's death approaches the Circus of Nights arrives and the people are drawn to it like moths to a flame. Soon they can talk of little else: it's as though they are bewitched. But Nick, John, Chris and Alan soon realise that there is something terribly wrong. And as the town is enclosed in a barrier of 'sickness' through which no one can enter or leave, the four men must do their utmost to protect their loved ones, before it is too late.