The Puma is the only character in the story who is depicted undergoing the transformation from animal to Beast Folk. For most of the story, only the Puma’s screams are heard as it undergoes vivisection. Even so, Prendick can sense those screams becoming more and more human as the process goes on over several days, initially leading him to believe that Moreau is vivisecting human beings. Ultimately, the Puma breaks free from Moreau’s laboratory and kills Moreau, leading to the collapse of the Beast Folk’s society.