Narrated by Joaquin Phoenix, this film sets out to document how humans use animals across five industries: pets, food, clothing, entertainment, and scientific research. Hidden cameras and undercover footage follow animals through factory farms, slaughterhouses, fur farms, circuses, and research labs, tracking the gap between how these industries present themselves and what actually happens on the killing floor and in the cage. The film uses the term speciesism throughout, arguing that the same logic once used to justify racism and sexism now justifies how animals are treated, and it structures each chapter around that comparison. Footage includes puppy mills, veal crates, and animals being skinned for fur, shown largely without dramatization or interviews to soften it. The pacing is methodical rather than sensational, moving industry by industry and letting the footage make the argument on its own. It became a reference point for the animal rights movement after release, credited by several prominent activists as the film that changed how they eat and what they buy.