Having been nearly ruined by an investment scam, Dale Wilson, the driven President of GeoCore Oil Explorations, brings in young Colin Harper to help rebuild his company's credibility. But Wilson is still receiving death threats, now possibly from fanatics opposing his project to drill on land that's home to the Kluane tribe; these rights were won when younger Kluanes convinced their elders to sell a chunk of the territory. Testing soil from the region, GeoCore lab technician Reuben Galeno is frustrated when there is no indication of crude oil in the sample. Then, he begins to convulse, loses all body fluids and immediately turns into a mummified corpse. After the body is discovered by Jessica Wilson í¹€í·¥oCore's head of research, the President's daughter and Colin Harper's lover í¹ƒí´¨e OSIR is brought in to investigate.
Meanwhile, young Kluane native Winston Lucas arrives at the GeoCore building in search of soil samples. But when he drops a sample container, exposing the soil, he meets the same gruesome fate as Galeno. A level-three quarantine is ordered for those remaining in the building í¹€í´¯nner, Axon, Jessica, Colin Harper and Dale Wilson, who accuses the OSIR of being behind the deaths.
Watching Lucas' actions is another young native, Cocheta, who is the Shaman, the keeper of the ancient flame for the Kluane council of elders. She believes the soil has released an evil curse and that Lucas had attempted to return it to its original home, a sacred burial ground. Lending credence is Stone's discovery of ritualistic cave drawings í¹‚í´¥picting a dark serpent hovering over mummified corpses í¹ƒí´¨at hint of an ancient curse, apparently reactivated by the recent drilling.
Autopsy reports on Galeno and Lucas prove they had been attacked in the neural emotional control center, as if the entity waits for its host's emotional state to rise to feed on the adrenaline rush. Stone realizes they must all stay completely calm, or risk death. But Harper and Jessica aren't warned in time: stuck in quarantine, they disappear to make love. When Harper's body hits a fever pitch, he meets the same hideous demise as the others í¹‚í±®d the OSIR watch a snake-shaped organism slither out of his ear and quickly evaporate.
The GeoCore executives and OSIR agents now race against time: with three deaths to its evil credit, the evil force could now be inside any of them, waiting to feed on the rush of adrenaline. The only way to purge it is through a native cleansing ceremony: while all participants will experience great physical and emotional pain as their souls are cleansed, the person í¹‚í¿² persons í¹ƒí·¨o host the beast will hopefully expel it. And live.