Mr. Harris was the principal of Paradise High School at the time that Number Four attended.
He is described as fat, with his belly reaching over his belt, and mostly bald. He had small beady eyes, set too close together, that seemed to be swallowed when he smiled.
Mr Harris welcomes John to the school when he arrives. Despite his intial friendliness, however, it is clear that Mr. Harris favours certain students including Mark James, the talented star of the football team. He believes Mark's version of the meatball incident in the cafeteria.
When Mr. Harris learns of the rumours that John saved Sarah from the fire at Mark's house, he seems happy about the media attention. John (Four) is scared when he finds that he is the centre of the news story and smashes through the window of Mr Harris' office and runs away.
After the destruction of the school, Mark asks special permission to drive to Helena High by himself, rather than take the bus, so that he can maintain his fitness at the school's facilities. Mr. Harris agrees and Mark speculates it is because he hopes that anything he does in the future will make Paradise look good.
- Mr. Harris is portrayed by Garrett M Brown in the film adaptation of I Am Number Four, however he is credited as "Principal Simms".