Instinct

Years after he goes missing in the jungles of Africa, anthropologist Ethan Powell (Anthony Hopkins) resurfaces when it's discovered that he has murdered two poachers who were killing the gorillas he was studying. After spending an extended time living with the primates and without any human contact, Powell seems to be unhinged, and psychiatrist Theo Caulder (Cuba Gooding Jr.) is called in to try to get through to the withdrawn and angry man -- who may be wiser and saner than he appears.