‘Dog’s Purpose’ author defends set treatment: ‘The dog was not terrified’ W. Bruce Cameron writes on Facebook: ‘The written commentary accompanying the edited video mischaracterizes what happened.’ Check out this story on USATODAY.com: http://usat.ly/2ka1Lcs A Dog’s Purpose author W. Bruce Cameron is staunchly defending the movie adaptation’s set treatment of a German Shepherd named Hercules following outcry over a video release which showed the dog in distress while shooting a scene.