An adventurous photojournalist, Ted (MICHAEL PARE) has always responded to the call of the wild, traveling to the ends of the earth to capture his images. On one of his expeditions deep in the jungles of Nepal, he encounters a horrific, half-human beast that savagely murders his girlfriend. In a violent battle, Ted manages to blow the creature's head off -- but not before he receives a vicious bite that leaves him scarred forever... in more ways than one.
After his devastating journey, Ted returns to the pastoral Pacific Northwest, welcomed back to the inviting home of his sister, Janet (MARIEL HEMINGWAY), and his beloved 10-year-old nephew, Brett (MASON GAMBLE). Although Janet encourages Ted to move onto their picturesque property on the edge of a dense forest, she notices a disturbing change in her brother: he has a furtive way of avoiding her questions and a strange glint in his eye.
Janet isn't the only one in the family who notices a difference in Ted. While Brett is overjoyed to reunite with his uncle, it is Thor, the family's intuitive, protective German Shepherd, who senses a threat in the man he has always trusted.
When the murdered body of a hiker is discovered near the lake where Ted has been staying, Janet doesn't make a connection. But Thor does...and a deadly battle of wills begins.