If there’s anything worse than a movie hammered together out of pieces of bad screenplays, it’s a movie made from the scraps of good ones. At least with the trash we don’t have to suffer through the noble intentions. Instinct is a film with not one but four worthy themes. It has pious good thoughts about all of them, but undermines them by slapping on obligatory plot requirements, thick. Nothing happens in this movie that has not been sanctioned by long usage in better films. This is a film about (1) why Man should learn to live in harmony with nature; (2) why prison reform is necessary; (3) how fathers can learn to love their children; (4) why it is wrong to imprison animals in zoos. It doesn’t free the beasts from their cages, but it’s able to resolve the other three issues–unconvincingly, in a rush of hokey final scenes. — Roger Ebert

— You’ve been charged with one count of murder and found incompetent to stand trial.
— My neighbour had a demon in her for a while. It would come and go. Nobody saw it except me.
— What did it look like, the demon?
— Did you ever see Alien with Sigourney Weaver?
— It looked like a giant insect?
— No. It looked like Sigourney Weaver.