Ted (Michael Pare) is working in Nepal when he and his girlfriend are attacked by a mysterious creature. Ted, though brutally maimed, survives, but his girlfriend is not so lucky. To help his recovery, Ted moves close to his sister, Janet (Mariel Hemingway), and her son, Brett (Mason Gamble), but soon realizes he was attacked by a werewolf. Ted is helpless to stop his transformation and only Brett's German shepherd, Thor, is able to see that Ted is a danger to everyone around him.
