When the daughter of a US senator disappears from the center of Kodiak, Alaska, in the middle of the day, FBI agent Nick Morgan arrives to assist police detective Maureen Horner and Alaska State Trooper Dan Patterson with the investigation. Soon, the officers realize that other young people have vanished from the area as well, and they can find no evidence or eyewitnesses to explain the disappearances. Meanwhile, bored pilot Steve Larson spends his evenings sitting on the back deck of his floatplane air charter service while he recovers from a debilitating illness. He watches a plane land after dark and sees two men escort a seemingly incapacitated woman to the plane and push her into the rear seat. When the same thing happens a few days later, Steve wonders if he's imagining things or if these men are kidnapping people. He calls marine biologist and amateur detective Jane Marcus and asks her to sit with him the next time the plane arrives. Jane agrees with Steve: these men are drugging and transporting people against their will. But where are they taking them, and why? Jane's curiosity leads her into a nightmare worse than anything she could imagine. As law enforcement officers work to find who's behind the kidnappings and where the abductors have taken the victims, Jane fights to survive the monsters chasing her in the ultimate hunt.