Title: Monkey Shines
When Allan becomes a quadriplegic he loses all hope for living until he meets Ella - a monkey trained to fetch and carry for him around the house, obeying him in all things. But Ella is part of another experiment, and when she starts responding to Allan's underlying rage and frustration she has the ability to carry out her master's darkest wishes.
George A. Romero
Michael Stewart (novel), George A. Romero (screenplay)