Reclusive outdoorsman, Jimmy Kerrigan, finds himself battling a vampiric plague which threatens to destroy Hobson's Valley, the isolated mountain community he calls home. When his family, friends and neighbours fall prey to the `Fugue', Kerrigan is the only one who can save them and prevent the disease spreading beyond the remote town's boundaries.
Kerrigan is uniquely equipped to deal with the outbreak. He carries a variant strain of Fugue enabling him to overcome and heal its victims. However, the nature of the illness ensures neither he nor those he hunts down are aware they're infected. After feeding on humans, the diseased forget their behaviour. Even Kerrigan, having confronted or neutralised a Fugue, is unable to recall his actions as guardian of Hobson's Valley.
The illness and its effects have, like tetanus, survived in the earth around the mountain for countless generations. The lineage of Fugue Hunters has always been able to reverse an outbreak but not this time; someone wants the disease to spread and, in combination with a mutation of the virus, Kerrigan realises he may not be strong enough to contain it.
Kerrigan is challenged beyond his limits when an innocent family of outsiders hikes straight into a wilderness crawling with Fugues - a wilderness he is responsible for. Can he really save them and protect the town? Can he defeat the creature who has caused the Fugue to mutate? And, most crucially, when he learns the horrifying truth about his own infection, will he even have the strength to try?