It’s been years since I’ve read the book or seen the movie, but I had the exact opposite impression of the book vs the movie. The book is very deep, I found it compared rather well to dystopian novels like 1984. The movie, by contrast, felt like a weird slasher film, more interested in gratuitous violence than telling a compelling story. The characters in the book felt more nuanced. For example, the main female antagonist (I can’t remember her name) was a victim of abuse, and her trauma motivates her drive to live and her lack of hesitation to manipulating others to survive. Maybe someone else who has read the book here has a different take away?