- The Cast - Voice Artists Eli Marienthal is the Voice of Hogarth... a nine year old boy who dreams about saving the world from aliens. When he finds a 50 foot robot in his backyard it's up to him to save the iron giant from the government! In the process Hogarth teaches the robot to speak and what it's like to be human. Marienthal, a young actor (Jack Frost, and Slums of Beverly Hills) is a ...www.animationartist.com/movies/irongiant/Artists/Voice_Artists/voice_artists.html