Student Jane (Elisabeth Shue) works as an assistant for animal researcher Phillip (Terence Stamp) in an old house. They live alone except for the chimpanzees and Link, an intelligent, 45-year-old orangutan. Phillip wants to put Link to death, but before he can do this Link escapes one morning. Link starts behaving more and more aggressive and prohibits Jane from using the phone or reaching the next village. When she punishes him by locking him out, he becomes violent.